diff --git a/swad_ID.c b/swad_ID.c
index d93d851a4..af742cc73 100644
--- a/swad_ID.c
+++ b/swad_ID.c
@@ -606,8 +606,8 @@ static void ID_ShowFormChangeUsrID (const struct UsrData *UsrDat,
 	 HTM_TR_Begin (NULL);
 
 	 HTM_TD_Begin ("class=\"REC_C1_BOT RT\"");
-	 fprintf (Gbl.F.Out,"<label for=\"UsrID\" class=\"%s\">",
-		  The_ClassFormInBox[Gbl.Prefs.Theme]);
+	 HTM_LABEL_Begin ("for=\"UsrID\" class=\"%s\"",
+		          The_ClassFormInBox[Gbl.Prefs.Theme]);
 	 fprintf (Gbl.F.Out,"%s:",Txt_ID);
 	 HTM_LABEL_End ();
 	 HTM_TD_End ();
@@ -687,8 +687,8 @@ static void ID_ShowFormChangeUsrID (const struct UsrData *UsrDat,
       HTM_TR_Begin (NULL);
 
       HTM_TD_Begin ("class=\"REC_C1_BOT RT\"");
-      fprintf (Gbl.F.Out,"<label for=\"NewID\" class=\"%s\">",
-	       The_ClassFormInBox[Gbl.Prefs.Theme]);
+      HTM_LABEL_Begin ("for=\"NewID\" class=\"%s\"",
+	               The_ClassFormInBox[Gbl.Prefs.Theme]);
       fprintf (Gbl.F.Out,"%s:",
 	       UsrDat->IDs.Num ? Txt_Another_ID :	// A new user's ID
 		                 Txt_ID);		// The first user's ID
diff --git a/swad_account.c b/swad_account.c
index 55214ea2f..1594241a4 100644
--- a/swad_account.c
+++ b/swad_account.c
@@ -149,7 +149,7 @@ static void Acc_ShowFormCheckIfIHaveAccount (const char *Title)
 
    /***** Form to request user's ID for possible account already created *****/
    Frm_StartForm (ActChkUsrAcc);
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:&nbsp;"
 		      "<input type=\"text\" name=\"ID\""
 		      " size=\"18\" maxlength=\"%u\" value=\"\""
@@ -368,8 +368,7 @@ static void Acc_ShowFormRequestNewAccountWithParams (const char *NewNicknameWith
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"NewNick\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"NewNick\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Nickname);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -390,8 +389,7 @@ static void Acc_ShowFormRequestNewAccountWithParams (const char *NewNicknameWith
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"NewEmail\" class=\"%s\">",
-            The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"NewEmail\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Email);
    HTM_LABEL_End ();
    HTM_TD_End ();
diff --git a/swad_agenda.c b/swad_agenda.c
index da87d60bf..f8515d36f 100644
--- a/swad_agenda.c
+++ b/swad_agenda.c
@@ -1500,8 +1500,7 @@ void Agd_RequestCreatOrEditEvent (void)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"Event\" class=\"%s\">",
-            The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"Event\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Event);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -1519,8 +1518,7 @@ void Agd_RequestCreatOrEditEvent (void)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"Location\" class=\"%s\">",
-            The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"Location\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Location);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -1542,8 +1540,7 @@ void Agd_RequestCreatOrEditEvent (void)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RT\"");
-   fprintf (Gbl.F.Out,"<label for=\"Txt\" class=\"%s\">",
-            The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"Txt\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Description);
    HTM_LABEL_End ();
    HTM_TD_End ();
diff --git a/swad_announcement.c b/swad_announcement.c
index d70a270e8..bc4b54055 100644
--- a/swad_announcement.c
+++ b/swad_announcement.c
@@ -454,8 +454,7 @@ static void Ann_PutSubjectMessage (const char *Field,const char *Label,
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RT\"");
-   fprintf (Gbl.F.Out,"<label for=\"%s\" class=\"%s\">",
-	    Field,The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"%s\" class=\"%s\"",Field,The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Label);
    HTM_LABEL_End ();
    HTM_TD_End ();
diff --git a/swad_assignment.c b/swad_assignment.c
index 2d703a182..1af3c72d7 100644
--- a/swad_assignment.c
+++ b/swad_assignment.c
@@ -1167,8 +1167,7 @@ void Asg_RequestCreatOrEditAsg (void)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"Title\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"Title\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Title);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -1193,7 +1192,7 @@ void Asg_RequestCreatOrEditAsg (void)
    HTM_TD_End ();
 
    HTM_TD_Begin ("class=\"LM\"");
-   fprintf (Gbl.F.Out,"<label class=\"DAT\">");
+   HTM_LABEL_Begin ("class=\"DAT\"");
    fprintf (Gbl.F.Out,"%s:"
                       "<input type=\"text\" name=\"Folder\""
                       " size=\"30\" maxlength=\"%u\" value=\"%s\" />",
@@ -1208,8 +1207,7 @@ void Asg_RequestCreatOrEditAsg (void)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RT\"");
-   fprintf (Gbl.F.Out,"<label for=\"Txt\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"Txt\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Description);
    HTM_LABEL_End ();
    HTM_TD_End ();
diff --git a/swad_attendance.c b/swad_attendance.c
index 7afd739aa..9b520f813 100644
--- a/swad_attendance.c
+++ b/swad_attendance.c
@@ -1104,8 +1104,7 @@ void Att_RequestCreatOrEditAttEvent (void)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RT\"");
-   fprintf (Gbl.F.Out,"<label for=\"Title\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"Title\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Title);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -1126,8 +1125,7 @@ void Att_RequestCreatOrEditAttEvent (void)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RT\"");
-   fprintf (Gbl.F.Out,"<label for=\"ComTchVisible\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"ComTchVisible\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Teachers_comment);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -1155,8 +1153,7 @@ void Att_RequestCreatOrEditAttEvent (void)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RT\"");
-   fprintf (Gbl.F.Out,"<label for=\"Txt\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"Txt\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Description);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -2088,7 +2085,7 @@ static void Att_WriteRowUsrToCallTheRoll (unsigned NumUsr,
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"BT%u\"",Gbl.RowEvenOdd);
-   fprintf (Gbl.F.Out,"<label for=\"Std%u\">",NumUsr);
+   HTM_LABEL_Begin ("for=\"Std%u\"",NumUsr);
    Att_PutCheckOrCross (Present);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -3138,7 +3135,7 @@ static void Att_ListEventsToSelect (Att_TypeOfView_t TypeOfView)
       HTM_TD_End ();
 
       HTM_TD_Begin ("class=\"DAT RT COLOR%u\"",Gbl.RowEvenOdd);
-      fprintf (Gbl.F.Out,"<label for=\"Att%u\">",NumAttEvent);
+      HTM_LABEL_Begin ("for=\"Att%u\"",NumAttEvent);
       fprintf (Gbl.F.Out,"%u:",NumAttEvent + 1);
       HTM_LABEL_End ();
       HTM_TD_End ();
@@ -3146,7 +3143,7 @@ static void Att_ListEventsToSelect (Att_TypeOfView_t TypeOfView)
       if (asprintf (&Id,"att_date_start_%u",UniqueId) < 0)
 	 Lay_NotEnoughMemoryExit ();
       HTM_TD_Begin ("class=\"DAT LT COLOR%u\"",Gbl.RowEvenOdd);
-      fprintf (Gbl.F.Out,"<label for=\"Att%u\">",NumAttEvent);
+      HTM_LABEL_Begin ("for=\"Att%u\"",NumAttEvent);
       fprintf (Gbl.F.Out,"<span id=\"%s\"></span>",Id);
       HTM_LABEL_End ();
       Dat_WriteLocalDateHMSFromUTC (Id,Gbl.AttEvents.Lst[NumAttEvent].TimeUTC[Att_START_TIME],
diff --git a/swad_centre.c b/swad_centre.c
index f349f46ba..1724c2c17 100644
--- a/swad_centre.c
+++ b/swad_centre.c
@@ -413,8 +413,7 @@ static void Ctr_Configuration (bool PrintView)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"OthInsCod\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"OthInsCod\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Institution);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -457,8 +456,7 @@ static void Ctr_Configuration (bool PrintView)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"FullName\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"FullName\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Centre);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -490,8 +488,7 @@ static void Ctr_Configuration (bool PrintView)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"ShortName\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"ShortName\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Short_name);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -571,8 +568,7 @@ static void Ctr_Configuration (bool PrintView)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"WWW\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"WWW\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Web);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -2335,7 +2331,7 @@ void Ctr_RequestPhoto (void)
 		  Txt_XxY_pixels_or_higher);
 
    /***** Upload photo *****/
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:&nbsp;"
                       "<input type=\"file\" name=\"%s\" accept=\"image/*\""
                       " onchange=\"document.getElementById('%s').submit();\" />",
diff --git a/swad_changelog.h b/swad_changelog.h
index 8228bfff2..b5c39475b 100644
--- a/swad_changelog.h
+++ b/swad_changelog.h
@@ -496,7 +496,7 @@ ps2pdf source.ps destination.pdf
 // TODO: Importante: filtrar proyectos por usuarios (igual que en trabajos o en asistencia)
 // TODO: Buscar <label... y sustituir por HTM_LABEL_Begin ()
 
-	Version 19.51.2:  Nov 02, 2019	Code refactoring in HTML labels. (? lines)
+	Version 19.51.2:  Nov 02, 2019	Code refactoring in HTML labels. (246127 lines)
 	Version 19.51.1:  Nov 02, 2019	Code refactoring in HTML labels. Not finished. (246198 lines)
 	Version 19.51:    Nov 02, 2019	Code refactoring in HTML labels. Not finished. (246220 lines)
 	Version 19.50.4:  Nov 02, 2019	Code refactoring related with writing of local date-time. (246072 lines)
diff --git a/swad_course.c b/swad_course.c
index fa7d7987f..041267a0f 100644
--- a/swad_course.c
+++ b/swad_course.c
@@ -237,8 +237,7 @@ static void Crs_Configuration (bool PrintView)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"OthDegCod\" class=\"%s\">",
-            The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"OthDegCod\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Degree);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -283,8 +282,7 @@ static void Crs_Configuration (bool PrintView)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"FullName\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"FullName\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Course);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -316,8 +314,7 @@ static void Crs_Configuration (bool PrintView)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"ShortName\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"ShortName\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Short_name);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -350,8 +347,7 @@ static void Crs_Configuration (bool PrintView)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"OthCrsYear\" class=\"%s\">",
-            The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"OthCrsYear\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Year_OF_A_DEGREE);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -388,8 +384,7 @@ static void Crs_Configuration (bool PrintView)
       HTM_TR_Begin (NULL);
 
       HTM_TD_Begin ("class=\"RM\"");
-      fprintf (Gbl.F.Out,"<label for=\"InsCrsCod\" class=\"%s\">",
-	       The_ClassFormInBox[Gbl.Prefs.Theme]);
+      HTM_LABEL_Begin ("for=\"InsCrsCod\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
       fprintf (Gbl.F.Out,"%s:",Txt_Institutional_code);
       HTM_LABEL_End ();
       HTM_TD_End ();
@@ -3329,7 +3324,7 @@ void Crs_AskRemoveOldCrss (void)
                  Hlp_SYSTEM_Hierarchy_eliminate_old_courses,Box_NOT_CLOSABLE);
 
    /***** Form to request number of months without clicks *****/
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s&nbsp;"
 	              "<select name=\"Months\">",
             Txt_Eliminate_all_courses_whithout_users_PART_1_OF_2);
diff --git a/swad_date.c b/swad_date.c
index c40f8ee2b..50daa4b81 100644
--- a/swad_date.c
+++ b/swad_date.c
@@ -434,7 +434,7 @@ void Dat_PutFormStartEndClientLocalDateTimesWithYesterdayToday (bool SetHMS00000
 
    /***** Start date-time *****/
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_START_END_TIME[Dat_START_TIME]);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -467,7 +467,7 @@ void Dat_PutFormStartEndClientLocalDateTimesWithYesterdayToday (bool SetHMS00000
 
    /***** End date-time *****/
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_START_END_TIME[Dat_END_TIME]);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -512,7 +512,7 @@ void Dat_PutFormStartEndClientLocalDateTimes (time_t TimeUTC[2],
       HTM_TR_Begin (NULL);
 
       HTM_TD_Begin ("class=\"RM\"");
-      fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+      HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
       fprintf (Gbl.F.Out,"%s:",Txt_START_END_TIME[StartEndTime]);
       HTM_LABEL_End ();
       HTM_TD_End ();
diff --git a/swad_degree.c b/swad_degree.c
index 0bc8d4a2c..b0abd510d 100644
--- a/swad_degree.c
+++ b/swad_degree.c
@@ -342,8 +342,7 @@ static void Deg_Configuration (bool PrintView)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"OthCtrCod\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"OthCtrCod\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Centre);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -385,8 +384,7 @@ static void Deg_Configuration (bool PrintView)
    /***** Degree full name *****/
    HTM_TR_Begin (NULL);
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"FullName\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"FullName\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Degree);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -418,8 +416,7 @@ static void Deg_Configuration (bool PrintView)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"ShortName\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"ShortName\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Short_name);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -451,8 +448,7 @@ static void Deg_Configuration (bool PrintView)
    /***** Degree WWW *****/
    HTM_TR_Begin (NULL);
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"WWW\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"WWW\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Web);
    HTM_LABEL_End ();
    HTM_TD_End ();
diff --git a/swad_enrolment.c b/swad_enrolment.c
index e14bcaaf5..264731d13 100644
--- a/swad_enrolment.c
+++ b/swad_enrolment.c
@@ -377,8 +377,8 @@ void Enr_WriteFormToReqAnotherUsrID (Act_Action_t NextAction,void (*FuncParams)
    Frm_StartForm (NextAction);
    if (FuncParams)
       FuncParams ();
-   fprintf (Gbl.F.Out,"<label for=\"OtherUsrIDNickOrEMail\" class=\"%s RM\">",
-            The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"OtherUsrIDNickOrEMail\" class=\"%s RM\"",
+                    The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:&nbsp;",Txt_nick_email_or_ID);
    HTM_LABEL_End ();
    fprintf (Gbl.F.Out,"<input type=\"text\" id=\"OtherUsrIDNickOrEMail\""
@@ -804,7 +804,7 @@ void Enr_AskRemoveOldUsrs (void)
                  NULL,Box_NOT_CLOSABLE);
 
    /***** Form to request number of months without clicks *****/
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s&nbsp;",
             Txt_Eliminate_all_users_who_are_not_enroled_on_any_courses_PART_1_OF_2);
    fprintf (Gbl.F.Out,"<select name=\"Months\">");
@@ -921,8 +921,7 @@ static void Enr_PutAreaToEnterUsrsIDs (void)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RT\"");
-   fprintf (Gbl.F.Out,"<label for=\"UsrsIDs\" class=\"%s\">",
-            The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"UsrsIDs\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_List_of_nicks_emails_or_IDs);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -960,8 +959,8 @@ static void Enr_PutActionsRegRemSeveralUsrs (void)
 			 " name=\"RegRemAction\" value=\"%u\" checked=\"checked\" />",
       	       (unsigned) Enr_REGISTER_SPECIFIED_USRS_IN_CRS,
 	       (unsigned) Enr_REGISTER_SPECIFIED_USRS_IN_CRS);
-      fprintf (Gbl.F.Out,"<label for=\"RegRemAction%u\">",
-	       (unsigned) Enr_REGISTER_SPECIFIED_USRS_IN_CRS);
+      HTM_LABEL_Begin ("for=\"RegRemAction%u\"",
+	               (unsigned) Enr_REGISTER_SPECIFIED_USRS_IN_CRS);
       fprintf (Gbl.F.Out,"%s",Txt_Register_the_users_indicated_in_step_1);
       HTM_LABEL_End ();
       HTM_LI_End ();
@@ -971,8 +970,8 @@ static void Enr_PutActionsRegRemSeveralUsrs (void)
 			 " name=\"RegRemAction\" value=\"%u\" />",
 	       (unsigned) Enr_REMOVE_SPECIFIED_USRS_FROM_CRS,
 	       (unsigned) Enr_REMOVE_SPECIFIED_USRS_FROM_CRS);
-      fprintf (Gbl.F.Out,"<label for=\"RegRemAction%u\">",
-	       (unsigned) Enr_REMOVE_SPECIFIED_USRS_FROM_CRS);
+      HTM_LABEL_Begin ("for=\"RegRemAction%u\"",
+	               (unsigned) Enr_REMOVE_SPECIFIED_USRS_FROM_CRS);
       fprintf (Gbl.F.Out,"%s",Txt_Remove_the_users_indicated_in_step_1);
       HTM_LABEL_End ();
       HTM_LI_End ();
@@ -982,8 +981,8 @@ static void Enr_PutActionsRegRemSeveralUsrs (void)
 			 " name=\"RegRemAction\" value=\"%u\" />",
 	       (unsigned) Enr_REMOVE_NOT_SPECIFIED_USRS_FROM_CRS,
 	       (unsigned) Enr_REMOVE_NOT_SPECIFIED_USRS_FROM_CRS);
-      fprintf (Gbl.F.Out,"<label for=\"RegRemAction%u\">",
-	       (unsigned) Enr_REMOVE_NOT_SPECIFIED_USRS_FROM_CRS);
+      HTM_LABEL_Begin ("for=\"RegRemAction%u\"",
+	               (unsigned) Enr_REMOVE_NOT_SPECIFIED_USRS_FROM_CRS);
       fprintf (Gbl.F.Out,"%s",Txt_Remove_the_users_not_indicated_in_step_1);
       HTM_LABEL_End ();
       HTM_LI_End ();
@@ -993,8 +992,7 @@ static void Enr_PutActionsRegRemSeveralUsrs (void)
 			 " name=\"RegRemAction\" value=\"%u\" />",
 	       (unsigned) Enr_UPDATE_USRS_IN_CRS,
 	       (unsigned) Enr_UPDATE_USRS_IN_CRS);
-      fprintf (Gbl.F.Out,"<label for=\"RegRemAction%u\">",
-	       (unsigned) Enr_UPDATE_USRS_IN_CRS);
+      HTM_LABEL_Begin ("for=\"RegRemAction%u\"",(unsigned) Enr_UPDATE_USRS_IN_CRS);
       fprintf (Gbl.F.Out,"%s",
 	       Txt_Register_the_users_indicated_in_step_1_and_remove_the_users_not_indicated);
       HTM_LABEL_End ();
@@ -1009,8 +1007,8 @@ static void Enr_PutActionsRegRemSeveralUsrs (void)
                          " name=\"RegRemAction\" value=\"%u\" />",
                (unsigned) Enr_ELIMINATE_USRS_FROM_PLATFORM,
                (unsigned) Enr_ELIMINATE_USRS_FROM_PLATFORM);
-      fprintf (Gbl.F.Out,"<label for=\"RegRemAction%u\">",
-               (unsigned) Enr_ELIMINATE_USRS_FROM_PLATFORM);
+      HTM_LABEL_Begin ("for=\"RegRemAction%u\"",
+                       (unsigned) Enr_ELIMINATE_USRS_FROM_PLATFORM);
       fprintf (Gbl.F.Out,"%s",
                Txt_Eliminate_from_the_platform_the_users_indicated_in_step_1);
       HTM_LABEL_End ();
@@ -1771,8 +1769,7 @@ static void Enr_StartRegRemOneUsrAction (Enr_RegRemOneUsrAction_t RegRemOneUsrAc
       *OptionChecked = true;
      }
    fprintf (Gbl.F.Out," />");
-   fprintf (Gbl.F.Out,"<label for=\"RegRemAction%u\">",
-	    (unsigned) RegRemOneUsrAction);
+   HTM_LABEL_Begin ("for=\"RegRemAction%u\"",(unsigned) RegRemOneUsrAction);
   }
 
 static void Enr_EndRegRemOneUsrAction (void)
@@ -2292,8 +2289,7 @@ static void Enr_ShowEnrolmentRequestsGivenRoles (unsigned RolesSelected)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"ScopeEnr\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"ScopeEnr\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Scope);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -2308,7 +2304,7 @@ static void Enr_ShowEnrolmentRequestsGivenRoles (unsigned RolesSelected)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RT\"");
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Users);
    HTM_LABEL_End ();
    HTM_TD_End ();
diff --git a/swad_exam.c b/swad_exam.c
index 19687ba6e..a87ba7c9a 100644
--- a/swad_exam.c
+++ b/swad_exam.c
@@ -1092,7 +1092,7 @@ static void Exa_ShowExamAnnouncement (long ExaCod,
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RB\"");
-   fprintf (Gbl.F.Out,"<label for=\"CrsName\" class=\"%s\">",StyleForm);
+   HTM_LABEL_Begin ("for=\"CrsName\" class=\"%s\"",StyleForm);
    fprintf (Gbl.F.Out,"%s:",Txt_EXAM_ANNOUNCEMENT_Course);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -1115,7 +1115,7 @@ static void Exa_ShowExamAnnouncement (long ExaCod,
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RB\"");
-   fprintf (Gbl.F.Out,"<label for=\"Year\" class=\"%s\">",StyleForm);
+   HTM_LABEL_Begin ("for=\"Year\" class=\"%s\"",StyleForm);
    fprintf (Gbl.F.Out,"%s:",Txt_EXAM_ANNOUNCEMENT_Year_or_semester);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -1149,7 +1149,7 @@ static void Exa_ShowExamAnnouncement (long ExaCod,
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RB\"");
-   fprintf (Gbl.F.Out,"<label for=\"ExamSession\" class=\"%s\">",StyleForm);
+   HTM_LABEL_Begin ("for=\"ExamSession\" class=\"%s\"",StyleForm);
    fprintf (Gbl.F.Out,"%s:",Txt_EXAM_ANNOUNCEMENT_Session);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -1309,7 +1309,7 @@ static void Exa_ShowExamAnnouncement (long ExaCod,
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RT\"");
-   fprintf (Gbl.F.Out,"<label for=\"Place\" class=\"%s\">",StyleForm);
+   HTM_LABEL_Begin ("for=\"Place\" class=\"%s\"",StyleForm);
    fprintf (Gbl.F.Out,"%s:",Txt_EXAM_ANNOUNCEMENT_Place_of_exam);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -1337,7 +1337,7 @@ static void Exa_ShowExamAnnouncement (long ExaCod,
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RT\"");
-   fprintf (Gbl.F.Out,"<label for=\"ExamMode\" class=\"%s\">",StyleForm);
+   HTM_LABEL_Begin ("for=\"ExamMode\" class=\"%s\"",StyleForm);
    fprintf (Gbl.F.Out,"%s:",Txt_EXAM_ANNOUNCEMENT_Mode);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -1364,7 +1364,7 @@ static void Exa_ShowExamAnnouncement (long ExaCod,
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RT\"");
-   fprintf (Gbl.F.Out,"<label for=\"Structure\" class=\"%s\">",StyleForm);
+   HTM_LABEL_Begin ("for=\"Structure\" class=\"%s\"",StyleForm);
    fprintf (Gbl.F.Out,"%s:",Txt_EXAM_ANNOUNCEMENT_Structure_of_the_exam);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -1391,7 +1391,7 @@ static void Exa_ShowExamAnnouncement (long ExaCod,
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RT\"");
-   fprintf (Gbl.F.Out,"<label for=\"DocRequired\" class=\"%s\">",StyleForm);
+   HTM_LABEL_Begin ("for=\"DocRequired\" class=\"%s\"",StyleForm);
    fprintf (Gbl.F.Out,"%s:",Txt_EXAM_ANNOUNCEMENT_Documentation_required);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -1418,7 +1418,7 @@ static void Exa_ShowExamAnnouncement (long ExaCod,
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RT\"");
-   fprintf (Gbl.F.Out,"<label for=\"MatRequired\" class=\"%s\">",StyleForm);
+   HTM_LABEL_Begin ("for=\"MatRequired\" class=\"%s\"",StyleForm);
    fprintf (Gbl.F.Out,"%s:",Txt_EXAM_ANNOUNCEMENT_Material_required);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -1445,7 +1445,7 @@ static void Exa_ShowExamAnnouncement (long ExaCod,
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RT\"");
-   fprintf (Gbl.F.Out,"<label for=\"MatAllowed\" class=\"%s\">",StyleForm);
+   HTM_LABEL_Begin ("for=\"MatAllowed\" class=\"%s\"",StyleForm);
    fprintf (Gbl.F.Out,"%s:",Txt_EXAM_ANNOUNCEMENT_Material_allowed);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -1472,7 +1472,7 @@ static void Exa_ShowExamAnnouncement (long ExaCod,
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RT\"");
-   fprintf (Gbl.F.Out,"<label for=\"OtherInfo\" class=\"%s\">",StyleForm);
+   HTM_LABEL_Begin ("for=\"OtherInfo\" class=\"%s\"",StyleForm);
    fprintf (Gbl.F.Out,"%s:",Txt_EXAM_ANNOUNCEMENT_Other_information);
    HTM_LABEL_End ();
    HTM_TD_End ();
diff --git a/swad_figure.c b/swad_figure.c
index fe72a668e..4bb6e141f 100644
--- a/swad_figure.c
+++ b/swad_figure.c
@@ -205,7 +205,7 @@ void Fig_ReqShowFigures (void)
                  Hlp_ANALYTICS_Figures,Box_NOT_CLOSABLE);
 
    /***** Compute stats for anywhere, degree or course? *****/
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:&nbsp;",Txt_Scope);
    Gbl.Scope.Allowed = 1 << Hie_SYS |
 	               1 << Hie_CTY |
@@ -220,7 +220,7 @@ void Fig_ReqShowFigures (void)
    fprintf (Gbl.F.Out,"<br />");
 
    /***** Type of statistic *****/
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:&nbsp;"
 	              "<select name=\"FigureType\">",
 	    Txt_Statistic);
diff --git a/swad_file_browser.c b/swad_file_browser.c
index e41af79a2..f0022c1b8 100644
--- a/swad_file_browser.c
+++ b/swad_file_browser.c
@@ -8344,7 +8344,7 @@ static void Brw_PutFormToCreateAFolder (const char FileNameToShow[NAME_MAX + 1])
 	          FileNameToShow);
 
    /***** Folder *****/
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s: "
                       "<input type=\"text\" name=\"NewFolderName\""
                       " size=\"30\" maxlength=\"%u\" value=\"\""
@@ -8512,8 +8512,7 @@ static void Brw_PutFormToCreateALink (const char *FileNameToShow)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"NewLinkURL\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"NewLinkURL\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:&nbsp;",Txt_URL);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -8532,8 +8531,7 @@ static void Brw_PutFormToCreateALink (const char *FileNameToShow)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"NewLinkName\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"NewLinkName\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s&nbsp;(%s):&nbsp;",Txt_Save_as,Txt_optional);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -9586,8 +9584,8 @@ void Brw_ShowFileMetadata (void)
 	 HTM_TR_Begin (NULL);
 
 	 HTM_TD_Begin ("class=\"RM\"");
-	 fprintf (Gbl.F.Out,"<label for=\"PublicFile\" class=\"%s\">",
-		  The_ClassFormInBox[Gbl.Prefs.Theme]);
+	 HTM_LABEL_Begin ("for=\"PublicFile\" class=\"%s\"",
+		          The_ClassFormInBox[Gbl.Prefs.Theme]);
 	 fprintf (Gbl.F.Out,"%s:",Txt_Availability);
 	 HTM_LABEL_End ();
 	 HTM_TD_End ();
@@ -9621,8 +9619,8 @@ void Brw_ShowFileMetadata (void)
 	 HTM_TR_Begin (NULL);
 
 	 HTM_TD_Begin ("class=\"RM\"");
-	 fprintf (Gbl.F.Out,"<label for=\"License\" class=\"%s\">",
-		  The_ClassFormInBox[Gbl.Prefs.Theme]);
+	 HTM_LABEL_Begin ("for=\"License\" class=\"%s\"",
+		          The_ClassFormInBox[Gbl.Prefs.Theme]);
 	 fprintf (Gbl.F.Out,"%s:",Txt_License);
 	 HTM_LABEL_End ();
 	 HTM_TD_End ();
@@ -12152,7 +12150,7 @@ void Brw_AskRemoveOldFiles (void)
                  NULL,Box_NOT_CLOSABLE);
 
    /***** Form to request number of months (to remove files older) *****/
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s&nbsp;",Txt_Remove_files_older_than_PART_1_OF_2);
    fprintf (Gbl.F.Out,"<select name=\"Months\">");
    for (Months  = Brw_MIN_MONTHS_TO_REMOVE_OLD_FILES;
diff --git a/swad_forum.c b/swad_forum.c
index c0f9c6fda..b42ebe7c2 100644
--- a/swad_forum.c
+++ b/swad_forum.c
@@ -3905,8 +3905,7 @@ static void For_WriteFormForumPst (bool IsReply,const char *Subject)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"Subject\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"Subject\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_MSG_Subject);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -3927,8 +3926,7 @@ static void For_WriteFormForumPst (bool IsReply,const char *Subject)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RT\"");
-   fprintf (Gbl.F.Out,"<label for=\"Content\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"Content\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_MSG_Content);
    HTM_LABEL_End ();
    HTM_TD_End ();
diff --git a/swad_game.c b/swad_game.c
index bdf323a52..72cfed154 100644
--- a/swad_game.c
+++ b/swad_game.c
@@ -1139,8 +1139,7 @@ static void Gam_PutFormsEditionGame (struct Game *Game,bool ItsANewGame)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"Title\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"Title\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Title);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -1158,8 +1157,7 @@ static void Gam_PutFormsEditionGame (struct Game *Game,bool ItsANewGame)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RT\"");
-   fprintf (Gbl.F.Out,"<label for=\"Txt\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"Txt\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Description);
    HTM_LABEL_End ();
    HTM_TD_End ();
diff --git a/swad_group.c b/swad_group.c
index 0416c4357..86cfe3988 100644
--- a/swad_group.c
+++ b/swad_group.c
@@ -465,8 +465,7 @@ static void Grp_PutCheckboxAllGrps (Grp_WhichGroups_t GroupsSelectableByStdsOrNE
    else
       fprintf (Gbl.F.Out," disabled=\"disabled\"");
    fprintf (Gbl.F.Out," />");
-   fprintf (Gbl.F.Out,"<label for=\"AllGroups\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"AllGroups\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"&nbsp;%s",Txt_All_groups);
    HTM_LABEL_End ();
    HTM_DIV_End ();
@@ -2289,7 +2288,7 @@ static void Grp_ListGrpsForMultipleSelection (struct GroupType *GrpTyp,
 
    /* Group name = students with no group */
    HTM_TD_Begin ("class=\"DAT LM\"");
-   fprintf (Gbl.F.Out,"<label for=\"Grp%ld\">",-GrpTyp->GrpTypCod);
+   HTM_LABEL_Begin ("for=\"Grp%ld\"",-GrpTyp->GrpTypCod);
    fprintf (Gbl.F.Out,"%s",Txt_users_with_no_group);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -2397,7 +2396,7 @@ static void Grp_WriteRowGrp (struct Group *Grp,bool Highlight)
       HTM_TD_Begin ("class=\"LM LIGHT_BLUE\"");
    else
       HTM_TD_Begin ("class=\"LM\"");
-   fprintf (Gbl.F.Out,"<label for=\"Grp%ld\" class=\"DAT\">",Grp->GrpCod);
+   HTM_LABEL_Begin ("for=\"Grp%ld\" class=\"DAT\"",Grp->GrpCod);
    fprintf (Gbl.F.Out,"%s",Grp->GrpName);
    HTM_LABEL_End ();
    HTM_TD_End ();
diff --git a/swad_hierarchy.c b/swad_hierarchy.c
index 5df2ffd34..d75bf4363 100644
--- a/swad_hierarchy.c
+++ b/swad_hierarchy.c
@@ -103,8 +103,7 @@ void Hie_WriteMenuHierarchy (void)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"cty\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"cty\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Country);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -122,8 +121,7 @@ void Hie_WriteMenuHierarchy (void)
       HTM_TR_Begin (NULL);
 
       HTM_TD_Begin ("class=\"RM\"");
-      fprintf (Gbl.F.Out,"<label for=\"ins\" class=\"%s\">",
-	       The_ClassFormInBox[Gbl.Prefs.Theme]);
+      HTM_LABEL_Begin ("for=\"ins\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
       fprintf (Gbl.F.Out,"%s:",Txt_Institution);
       HTM_LABEL_End ();
       HTM_TD_End ();
@@ -141,8 +139,7 @@ void Hie_WriteMenuHierarchy (void)
          HTM_TR_Begin (NULL);
 
          HTM_TD_Begin ("class=\"RM\"");
-         fprintf (Gbl.F.Out,"<label for=\"ctr\" class=\"%s\">",
-		  The_ClassFormInBox[Gbl.Prefs.Theme]);
+         HTM_LABEL_Begin ("for=\"ctr\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
          fprintf (Gbl.F.Out,"%s:",Txt_Centre);
          HTM_LABEL_End ();
          HTM_TD_End ();
@@ -160,8 +157,8 @@ void Hie_WriteMenuHierarchy (void)
             HTM_TR_Begin (NULL);
 
 	    HTM_TD_Begin ("class=\"RM\"");
-	    fprintf (Gbl.F.Out,"<label for=\"deg\" class=\"%s\">",
-		     The_ClassFormInBox[Gbl.Prefs.Theme]);
+	    HTM_LABEL_Begin ("for=\"deg\" class=\"%s\"",
+			     The_ClassFormInBox[Gbl.Prefs.Theme]);
 	    fprintf (Gbl.F.Out,"%s:",Txt_Degree);
 	    HTM_LABEL_End ();
 	    HTM_TD_End ();
@@ -179,8 +176,8 @@ void Hie_WriteMenuHierarchy (void)
 	       HTM_TR_Begin (NULL);
 
 	       HTM_TD_Begin ("class=\"RM\"");
-	       fprintf (Gbl.F.Out,"<label for=\"crs\" class=\"%s\">",
-			The_ClassFormInBox[Gbl.Prefs.Theme]);
+	       HTM_LABEL_Begin ("for=\"crs\" class=\"%s\"",
+			        The_ClassFormInBox[Gbl.Prefs.Theme]);
 	       fprintf (Gbl.F.Out,"%s:",Txt_Course);
 	       HTM_LABEL_End ();
 	       HTM_TD_End ();
diff --git a/swad_indicator.c b/swad_indicator.c
index f276a23d6..3f892d97a 100644
--- a/swad_indicator.c
+++ b/swad_indicator.c
@@ -123,8 +123,7 @@ void Ind_ReqIndicatorsCourses (void)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"ScopeInd\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"ScopeInd\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Scope);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -139,8 +138,8 @@ void Ind_ReqIndicatorsCourses (void)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"OthDegTypCod\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"OthDegTypCod\" class=\"%s\"",
+	            The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Types_of_degree);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -159,8 +158,8 @@ void Ind_ReqIndicatorsCourses (void)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"%s\" class=\"%s\">",
-	    Dpt_PARAM_DPT_COD_NAME,The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"%s\" class=\"%s\"",
+	            Dpt_PARAM_DPT_COD_NAME,The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Department);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -680,7 +679,7 @@ static void Ind_ShowNumCoursesWithIndicators (unsigned NumCrssWithIndicatorYes[1
 	}
 
       HTM_TD_Begin ("class=\"%s\"",Class);
-      fprintf (Gbl.F.Out,"<label for=\"Indicators%u\">",Ind);
+      HTM_LABEL_Begin ("for=\"Indicators%u\"",Ind);
       fprintf (Gbl.F.Out,"%u",Ind);
       HTM_LABEL_End ();
       HTM_TD_End ();
diff --git a/swad_info.c b/swad_info.c
index 9061a8ffb..fb39fd0b9 100644
--- a/swad_info.c
+++ b/swad_info.c
@@ -1166,8 +1166,8 @@ void Inf_FormsToSelSendInfo (void)
 	 HTM_TD_Begin ("class=\"LT LIGHT_BLUE\"");
       else
 	 HTM_TD_Begin ("class=\"LT\"");
-      fprintf (Gbl.F.Out,"<label for=\"InfoSrc%u\" class=\"%s\">",
-	       (unsigned) InfoSrc,The_ClassFormInBox[Gbl.Prefs.Theme]);
+      HTM_LABEL_Begin ("for=\"InfoSrc%u\" class=\"%s\"",
+	               (unsigned) InfoSrc,The_ClassFormInBox[Gbl.Prefs.Theme]);
       fprintf (Gbl.F.Out,"%s",Txt_INFO_SRC_FULL_TEXT[InfoSrc]);
       HTM_LABEL_End ();
       if (Txt_INFO_SRC_HELP[InfoSrc])
@@ -1275,7 +1275,7 @@ void Inf_FormToSendPage (Inf_InfoSrc_t InfoSrc)
 
    /***** File *****/
    HTM_DIV_Begin ("class=\"CM\"");
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:&nbsp;"
                       "<input type=\"file\" name=\"%s\" />",
             Txt_File,
@@ -1310,7 +1310,7 @@ void Inf_FormToSendURL (Inf_InfoSrc_t InfoSrc)
 
    /***** Link *****/
    HTM_DIV_Begin ("class=\"CM\"");
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:&nbsp;"
                       "<input type=\"url\" name=\"InfoSrcURL\""
                       " size=\"50\" maxlength=\"256\" value=\"",
diff --git a/swad_institution.c b/swad_institution.c
index 6a8a16024..fc9aa7db5 100644
--- a/swad_institution.c
+++ b/swad_institution.c
@@ -354,8 +354,7 @@ static void Ins_Configuration (bool PrintView)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"OthCtyCod\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"OthCtyCod\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Country);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -398,8 +397,7 @@ static void Ins_Configuration (bool PrintView)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"FullName\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"FullName\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Institution);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -431,8 +429,7 @@ static void Ins_Configuration (bool PrintView)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"ShortName\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"ShortName\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Short_name);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -464,8 +461,7 @@ static void Ins_Configuration (bool PrintView)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"WWW\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"WWW\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Web);
    HTM_LABEL_End ();
    HTM_TD_End ();
diff --git a/swad_logo.c b/swad_logo.c
index 714c02ed4..a48e63f97 100644
--- a/swad_logo.c
+++ b/swad_logo.c
@@ -313,8 +313,7 @@ void Log_RequestLogo (Hie_Level_t Scope)
 	          64,64);
 
    /***** Upload logo *****/
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",
-            The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:&nbsp;"
                       "<input type=\"file\" name=\"%s\""
                       " onchange=\"document.getElementById('%s').submit();\" />",
diff --git a/swad_mail.c b/swad_mail.c
index 5778bb45e..9150701fa 100644
--- a/swad_mail.c
+++ b/swad_mail.c
@@ -1272,8 +1272,8 @@ static void Mai_ShowFormChangeUsrEmail (const struct UsrData *UsrDat,bool ItsMe,
 	{
 	 /* The first mail is the current one */
 	 HTM_TD_Begin ("class=\"REC_C1_BOT RT\"");
-	 fprintf (Gbl.F.Out,"<label for=\"Email\" class=\"%s\">",
-		  The_ClassFormInBox[Gbl.Prefs.Theme]);
+	 HTM_LABEL_Begin ("for=\"Email\" class=\"%s\"",
+		          The_ClassFormInBox[Gbl.Prefs.Theme]);
 	 fprintf (Gbl.F.Out,"%s:",Txt_Current_email);
 	 HTM_LABEL_End ();
 	 HTM_TD_End ();
@@ -1286,8 +1286,8 @@ static void Mai_ShowFormChangeUsrEmail (const struct UsrData *UsrDat,bool ItsMe,
 	   {
 	    HTM_TD_Begin ("rowspan=\"%u\" class=\"REC_C1_BOT RT\"",
 		          NumEmails - 1);
-	    fprintf (Gbl.F.Out,"<label for=\"Email\" class=\"%s\">",
-		     The_ClassFormInBox[Gbl.Prefs.Theme]);
+	    HTM_LABEL_Begin ("for=\"Email\" class=\"%s\"",
+		             The_ClassFormInBox[Gbl.Prefs.Theme]);
 	    fprintf (Gbl.F.Out,"%s:",Txt_Other_emails);
 	    HTM_LABEL_End ();
 	    HTM_TD_End ();
@@ -1374,8 +1374,8 @@ static void Mai_ShowFormChangeUsrEmail (const struct UsrData *UsrDat,bool ItsMe,
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"REC_C1_BOT RT\"");
-   fprintf (Gbl.F.Out,"<label for=\"NewEmail\" class=\"%s\">",
-            The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"NewEmail\" class=\"%s\"",
+                    The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",
             NumEmails ? Txt_New_email :	// A new email
         	        Txt_Email);	// The first email
diff --git a/swad_match.c b/swad_match.c
index c2ade85bd..f9e39fd37 100644
--- a/swad_match.c
+++ b/swad_match.c
@@ -1199,8 +1199,7 @@ static void Mch_PutFormNewMatch (struct Game *Game)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"Title\" class=\"%s\">",
-            The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"Title\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Title);
    HTM_LABEL_End ();
    HTM_TD_End ();
diff --git a/swad_message.c b/swad_message.c
index 8027a95a0..876110ac5 100644
--- a/swad_message.c
+++ b/swad_message.c
@@ -485,7 +485,7 @@ static void Msg_WriteFormUsrsIDsOrNicksOtherRecipients (void)
    HTM_TR_Begin (NULL);
 
    HTM_TH_Begin (1,ColSpan,"LM LIGHT_BLUE");
-   fprintf (Gbl.F.Out,"<label for=\"OtherRecipients\">");
+   HTM_LABEL_Begin ("for=\"OtherRecipients\"");
    fprintf (Gbl.F.Out,"%s:",StdsAndTchsWritten ? Txt_Other_recipients :
 				                 Txt_Recipients);
    HTM_LABEL_End ();
@@ -536,8 +536,8 @@ static void Msg_WriteFormSubjectAndContentMsgToUsrs (char Content[Cns_MAX_BYTES_
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RT\"");
-   fprintf (Gbl.F.Out,"<label for=\"MsgSubject\" class=\"%s\">",
-            The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"MsgSubject\" class=\"%s\"",
+                    The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_MSG_Subject);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -588,8 +588,8 @@ static void Msg_WriteFormSubjectAndContentMsgToUsrs (char Content[Cns_MAX_BYTES_
       HTM_TR_Begin (NULL);
 
       HTM_TD_Begin ("class=\"RT\"");
-      fprintf (Gbl.F.Out,"<label for=\"MsgContent\" class=\"%s\">",
-	       The_ClassFormInBox[Gbl.Prefs.Theme]);
+      HTM_LABEL_Begin ("for=\"MsgContent\" class=\"%s\"",
+	               The_ClassFormInBox[Gbl.Prefs.Theme]);
       fprintf (Gbl.F.Out,"%s:",Txt_MSG_Content);
       HTM_LABEL_End ();
       HTM_TD_End ();
@@ -624,8 +624,8 @@ static void Msg_WriteFormSubjectAndContentMsgToUsrs (char Content[Cns_MAX_BYTES_
       HTM_TR_Begin (NULL);
 
       HTM_TD_Begin ("class=\"RT\"");
-      fprintf (Gbl.F.Out,"<label for=\"MsgContent\" class=\"%s\">",
-               The_ClassFormInBox[Gbl.Prefs.Theme]);
+      HTM_LABEL_Begin ("for=\"MsgContent\" class=\"%s\"",
+                       The_ClassFormInBox[Gbl.Prefs.Theme]);
       fprintf (Gbl.F.Out,"%s:",Txt_MSG_Content);
       HTM_LABEL_End ();
       HTM_TD_End ();
@@ -2614,8 +2614,7 @@ void Msg_ShowFormSelectCourseSentOrRecMsgs (void)
      };
 
    /***** Course selection *****/
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",
-            The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s&nbsp;"
                       "<select name=\"FilterCrsCod\">"
                       "<option value=\"\"",
@@ -2661,7 +2660,7 @@ void Msg_ShowFormToFilterMsgs (void)
 
    /***** Filter authors/recipients *****/
    HTM_TD_Begin ("class=\"LM\"");
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:&nbsp;"
                       "<input type=\"search\" name=\"FilterFromTo\""
                       " size=\"20\" maxlength=\"%u\" value=\"%s\" />",
@@ -2672,7 +2671,7 @@ void Msg_ShowFormToFilterMsgs (void)
 
    /***** Filter message content *****/
    HTM_TD_Begin ("class=\"LM\"");
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:&nbsp;"
                       "<input type=\"search\" name=\"FilterContent\""
                       " size=\"20\" maxlength=\"%u\" value=\"%s\" />",
@@ -2697,7 +2696,7 @@ static void Msg_ShowFormToShowOnlyUnreadMessages (void)
    extern const char *Txt_only_unread_messages;
 
    /***** Put checkbox to select whether to show only unread (received) messages *****/
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"<input type=\"checkbox\" name=\"OnlyUnreadMsgs\""
 	              " value=\"Y\"");
    if (Gbl.Msg.ShowOnlyUnreadMsgs)
diff --git a/swad_network.c b/swad_network.c
index df9bca7c3..850ab8aeb 100644
--- a/swad_network.c
+++ b/swad_network.c
@@ -320,8 +320,8 @@ void Net_ShowFormMyWebsAndSocialNets (void)
       HTM_TR_Begin (NULL);
 
       HTM_TD_Begin ("class=\"REC_C1_BOT LM\"");
-      fprintf (Gbl.F.Out,"<label for=\"URL%u\" class=\"%s\">",
-	       (unsigned) NumURL,The_ClassFormInBox[Gbl.Prefs.Theme]);
+      HTM_LABEL_Begin ("for=\"URL%u\" class=\"%s\"",
+	               (unsigned) NumURL,The_ClassFormInBox[Gbl.Prefs.Theme]);
       HTM_IMG (Cfg_URL_ICON_PUBLIC,Net_WebsAndSocialNetworksIcons[NumURL],Net_WebsAndSocialNetworksTitle[NumURL],
 	       "class=\"CONTEXT_ICO_16x16\" style=\"margin-right:6px;\"");
       fprintf (Gbl.F.Out,"%s:",
diff --git a/swad_nickname.c b/swad_nickname.c
index 9d9511b94..93dbb4568 100644
--- a/swad_nickname.c
+++ b/swad_nickname.c
@@ -273,8 +273,7 @@ static void Nck_ShowFormChangeUsrNickname (const struct UsrData *UsrDat,bool Its
 	{
 	 /* The first nickname is the current one */
 	 HTM_TD_Begin ("class=\"REC_C1_BOT RT\"");
-	 fprintf (Gbl.F.Out,"<label for=\"Nick\" class=\"%s\">",
-		  The_ClassFormInBox[Gbl.Prefs.Theme]);
+	 HTM_LABEL_Begin ("for=\"Nick\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
 	 fprintf (Gbl.F.Out,"%s:",Txt_Current_nickname);
 	 HTM_LABEL_End ();
 	 HTM_TD_End ();
@@ -287,8 +286,8 @@ static void Nck_ShowFormChangeUsrNickname (const struct UsrData *UsrDat,bool Its
 	   {
 	    HTM_TD_Begin ("rowspan=\"%u\" class=\"REC_C1_BOT RT\"",
 		          NumNicks - 1);
-	    fprintf (Gbl.F.Out,"<label for=\"Nick\" class=\"%s\">",
-		     The_ClassFormInBox[Gbl.Prefs.Theme]);
+	    HTM_LABEL_Begin ("for=\"Nick\" class=\"%s\"",
+		             The_ClassFormInBox[Gbl.Prefs.Theme]);
 	    fprintf (Gbl.F.Out,"%s:",Txt_Other_nicknames);
 	    HTM_LABEL_End ();
 	    HTM_TD_End ();
@@ -370,8 +369,7 @@ static void Nck_ShowFormChangeUsrNickname (const struct UsrData *UsrDat,bool Its
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"REC_C1_BOT RT\"");
-   fprintf (Gbl.F.Out,"<label for=\"NewNick\" class=\"%s\">",
-            The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"NewNick\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",
             NumNicks ? Txt_New_nickname :	// A new nickname
         	       Txt_Nickname);		// The first nickname
diff --git a/swad_password.c b/swad_password.c
index 3e3a16c46..de59f6c85 100644
--- a/swad_password.c
+++ b/swad_password.c
@@ -282,7 +282,7 @@ void Pwd_ShowFormSendNewPwd (void)
    Ale_ShowAlert (Ale_INFO,Txt_If_you_have_forgotten_your_password_);
 
    /***** User's ID/nickname *****/
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:&nbsp;"
                       "<input type=\"text\" name=\"UsrId\""
                       " size=\"8\" maxlength=\"%u\" value=\"%s\""
@@ -688,8 +688,7 @@ void Pwd_ShowFormChgMyPwd (void)
       HTM_TR_Begin (NULL);
 
       HTM_TD_Begin ("class=\"REC_C1_BOT RM\"");
-      fprintf (Gbl.F.Out,"<label for=\"UsrPwd\" class=\"%s\">",
-	       The_ClassFormInBox[Gbl.Prefs.Theme]);
+      HTM_LABEL_Begin ("for=\"UsrPwd\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
       fprintf (Gbl.F.Out,"%s:",Txt_Current_password);
       HTM_LABEL_End ();
       HTM_TD_End ();
@@ -742,8 +741,7 @@ void Pwd_PutFormToGetNewPasswordOnce (void)
 
    /***** Begin form element ****/
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"Passwd\" class=\"%s\">",
-            The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"Passwd\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Password);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -780,8 +778,7 @@ void Pwd_PutFormToGetNewPasswordTwice (void)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"REC_C1_BOT RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"Paswd1\" class=\"%s\">",
-            The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"Paswd1\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_New_password);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -806,8 +803,7 @@ void Pwd_PutFormToGetNewPasswordTwice (void)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"REC_C1_BOT RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"Paswd2\" class=\"%s\">",
-            The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"Paswd2\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Retype_new_password);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -893,13 +889,13 @@ void Pwd_AskForConfirmationOnDangerousAction (void)
    extern const char *Txt_For_security_enter_your_password;
 
    HTM_DIV_Begin ("class=\"CM\" style=\"margin:12px;\"");
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"<input type=\"checkbox\" name=\"Consent\" value=\"Y\" />"
 		      "%s",
 	    Txt_I_understand_that_this_action_can_not_be_undone);
    HTM_LABEL_End ();
    fprintf (Gbl.F.Out,"<br />");
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:&nbsp;"
 		      "<input type=\"password\" name=\"OthUsrPwd\""
 		      " size=\"16\" maxlength=\"%u\""
diff --git a/swad_photo.c b/swad_photo.c
index 1956e8762..153660ebe 100644
--- a/swad_photo.c
+++ b/swad_photo.c
@@ -335,7 +335,7 @@ static void Pho_ReqPhoto (const struct UsrData *UsrDat)
    Ale_ShowAlert (Ale_INFO,Txt_You_can_send_a_file_with_an_image_in_JPEG_format_);
 
    /***** Form to upload photo *****/
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:&nbsp;"
                       "<input type=\"file\" name=\"%s\" accept=\"image/*\""
                       " onchange=\"document.getElementById('%s').submit();\" />",
@@ -1790,8 +1790,7 @@ static void Pho_PutSelectorForTypeOfAvg (void)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"AvgType\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"AvgType\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Average_type);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -1856,8 +1855,7 @@ static void Pho_PutSelectorForHowComputePhotoSize (void)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"PhotoSize\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"PhotoSize\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Size_of_photos);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -1922,8 +1920,7 @@ static void Pho_PutSelectorForHowOrderDegrees (void)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"Order\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"Order\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Sort_degrees_by);
    HTM_LABEL_End ();
    HTM_TD_End ();
diff --git a/swad_profile.c b/swad_profile.c
index 32cb77d5a..e74d31755 100644
--- a/swad_profile.c
+++ b/swad_profile.c
@@ -204,7 +204,7 @@ void Prf_RequestUserProfile (void)
    /***** Form to request user's @nickname *****/
    /* By default, the nickname is filled with my nickname
       If no user logged ==> the nickname is empty */
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:&nbsp;"
                       "<input type=\"text\" name=\"usr\""
                       " size=\"18\" maxlength=\"%u\" value=\"@%s\" />",
diff --git a/swad_project.c b/swad_project.c
index d74bed744..b03239e53 100644
--- a/swad_project.c
+++ b/swad_project.c
@@ -3299,8 +3299,7 @@ static void Prj_PutFormProject (struct Project *Prj,bool ItsANewProject)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"Title\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"Title\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Title);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -3318,9 +3317,9 @@ static void Prj_PutFormProject (struct Project *Prj,bool ItsANewProject)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"%s\" class=\"%s\">",
-	    Dpt_PARAM_DPT_COD_NAME,
-            The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"%s\" class=\"%s\"",
+		    Dpt_PARAM_DPT_COD_NAME,
+                    The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Department);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -3419,8 +3418,7 @@ static void Prj_PutFormProject (struct Project *Prj,bool ItsANewProject)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"WWW\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"WWW\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_URL);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -3459,8 +3457,7 @@ static void Prj_EditOneProjectTxtArea (const char *Id,
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RT\"");
-   fprintf (Gbl.F.Out,"<label for=\"%s\" class=\"%s\">",
-	    Id,The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"%s\" class=\"%s\"",Id,The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Label);
    HTM_LABEL_End ();
    HTM_TD_End ();
diff --git a/swad_record.c b/swad_record.c
index c3d5c9d60..709846b52 100644
--- a/swad_record.c
+++ b/swad_record.c
@@ -1495,7 +1495,7 @@ static void Rec_ShowLinkToPrintPreviewOfRecords (void)
    Ico_PutIconTextLink ("print.svg",
 			Txt_Print);
    Frm_LinkFormEnd ();
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"(<select name=\"RecsPerPag\">");
    for (i = Rec_MIN_RECORDS_PER_PAGE;
         i <= Rec_MAX_RECORDS_PER_PAGE;
@@ -2914,7 +2914,7 @@ static void Rec_ShowRole (struct UsrData *UsrDat,
       Rol_GetRolesInAllCrssIfNotYetGot (UsrDat);
 
       HTM_TD_Begin ("class=\"REC_C1_BOT RM\"");
-      fprintf (Gbl.F.Out,"<label for=\"Role\" class=\"%s\">",ClassForm);
+      HTM_LABEL_Begin ("for=\"Role\" class=\"%s\"",ClassForm);
       fprintf (Gbl.F.Out,"%s:",Txt_Role);
       HTM_LABEL_End ();
       HTM_TD_End ();
@@ -3121,7 +3121,7 @@ static void Rec_ShowRole (struct UsrData *UsrDat,
 	   Sex <= Usr_SEX_MALE;
 	   Sex++)
 	{
-	 fprintf (Gbl.F.Out,"<label class=\"REC_DAT_BOLD\">");
+	 HTM_LABEL_Begin ("class=\"REC_DAT_BOLD\"");
 	 fprintf (Gbl.F.Out,"<input type=\"radio\" name=\"Sex\" value=\"%u\"",
 	          (unsigned) Sex);
 	 if (Sex == Gbl.Usrs.Me.UsrDat.Sex)
@@ -3163,7 +3163,7 @@ static void Rec_ShowSurname1 (struct UsrData *UsrDat,
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"REC_C1_BOT RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"Surname1\" class=\"%s\">",ClassForm);
+   HTM_LABEL_Begin ("for=\"Surname1\" class=\"%s\"",ClassForm);
    fprintf (Gbl.F.Out,"%s",Txt_Surname_1);
    if (TypeOfView == Rec_SHA_MY_RECORD_FORM)
       fprintf (Gbl.F.Out,"*");
@@ -3204,7 +3204,7 @@ static void Rec_ShowSurname2 (struct UsrData *UsrDat,
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"REC_C1_BOT RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"Surname2\" class=\"%s\">",ClassForm);
+   HTM_LABEL_Begin ("for=\"Surname2\" class=\"%s\"",ClassForm);
    fprintf (Gbl.F.Out,"%s:",Txt_Surname_2);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -3238,7 +3238,7 @@ static void Rec_ShowFirstName (struct UsrData *UsrDat,
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"REC_C1_BOT RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"FirstName\" class=\"%s\">",ClassForm);
+   HTM_LABEL_Begin ("for=\"FirstName\" class=\"%s\"",ClassForm);
    fprintf (Gbl.F.Out,"%s",Txt_First_name);
    if (TypeOfView == Rec_SHA_MY_RECORD_FORM)
       fprintf (Gbl.F.Out,"*");
@@ -3288,7 +3288,7 @@ static void Rec_ShowCountry (struct UsrData *UsrDat,
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"REC_C1_BOT RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"OthCtyCod\" class=\"%s\">",ClassForm);
+   HTM_LABEL_Begin ("for=\"OthCtyCod\" class=\"%s\"",ClassForm);
    fprintf (Gbl.F.Out,"%s",Txt_Country);
    if (TypeOfView == Rec_SHA_MY_RECORD_FORM)
       fprintf (Gbl.F.Out,"*");
@@ -3337,7 +3337,7 @@ static void Rec_ShowOriginPlace (struct UsrData *UsrDat,
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"REC_C1_BOT RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"OriginPlace\" class=\"%s\">",ClassForm);
+   HTM_LABEL_Begin ("for=\"OriginPlace\" class=\"%s\"",ClassForm);
    fprintf (Gbl.F.Out,"%s:",Txt_Place_of_origin);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -3406,7 +3406,7 @@ static void Rec_ShowLocalAddress (struct UsrData *UsrDat,
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"REC_C1_BOT RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"LocalAddress\" class=\"%s\">",ClassForm);
+   HTM_LABEL_Begin ("for=\"LocalAddress\" class=\"%s\"",ClassForm);
    fprintf (Gbl.F.Out,"%s:",Txt_Local_address);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -3442,7 +3442,7 @@ static void Rec_ShowLocalPhone (struct UsrData *UsrDat,
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"REC_C1_BOT RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"LocalPhone\" class=\"%s\">",ClassForm);
+   HTM_LABEL_Begin ("for=\"LocalPhone\" class=\"%s\"",ClassForm);
    fprintf (Gbl.F.Out,"%s:",Txt_Phone);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -3482,7 +3482,7 @@ static void Rec_ShowFamilyAddress (struct UsrData *UsrDat,
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"REC_C1_BOT RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"FamilyAddress\" class=\"%s\">",ClassForm);
+   HTM_LABEL_Begin ("for=\"FamilyAddress\" class=\"%s\"",ClassForm);
    fprintf (Gbl.F.Out,"%s:",Txt_Family_address);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -3518,7 +3518,7 @@ static void Rec_ShowFamilyPhone (struct UsrData *UsrDat,
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"REC_C1_BOT RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"FamilyPhone\" class=\"%s\">",ClassForm);
+   HTM_LABEL_Begin ("for=\"FamilyPhone\" class=\"%s\"",ClassForm);
    fprintf (Gbl.F.Out,"%s:",Txt_Phone);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -3558,7 +3558,7 @@ static void Rec_ShowComments (struct UsrData *UsrDat,
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"REC_C1_BOT RT\"");
-   fprintf (Gbl.F.Out,"<label for=\"Comments\" class=\"%s\">",ClassForm);
+   HTM_LABEL_Begin ("for=\"Comments\" class=\"%s\"",ClassForm);
    fprintf (Gbl.F.Out,"%s:",Txt_USER_comments);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -4038,7 +4038,7 @@ static void Rec_ShowFormMyInsCtrDpt (bool IAmATeacher)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"REC_C1_BOT RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"OthCtyCod\" class=\"%s\">",ClassForm);
+   HTM_LABEL_Begin ("for=\"OthCtyCod\" class=\"%s\"",ClassForm);
    fprintf (Gbl.F.Out,"%s*:",Txt_Country);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -4083,7 +4083,7 @@ static void Rec_ShowFormMyInsCtrDpt (bool IAmATeacher)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"REC_C1_BOT RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"OthInsCod\" class=\"%s\">",ClassForm);
+   HTM_LABEL_Begin ("for=\"OthInsCod\" class=\"%s\"",ClassForm);
    fprintf (Gbl.F.Out,"%s*:",Txt_Institution);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -4133,7 +4133,7 @@ static void Rec_ShowFormMyInsCtrDpt (bool IAmATeacher)
       HTM_TR_Begin (NULL);
 
       HTM_TD_Begin ("class=\"REC_C1_BOT RM\"");
-      fprintf (Gbl.F.Out,"<label for=\"OthCtrCod\" class=\"%s\">",ClassForm);
+      HTM_LABEL_Begin ("for=\"OthCtrCod\" class=\"%s\"",ClassForm);
       fprintf (Gbl.F.Out,"%s*:",Txt_Centre);
       HTM_LABEL_End ();
       HTM_TD_End ();
@@ -4181,8 +4181,7 @@ static void Rec_ShowFormMyInsCtrDpt (bool IAmATeacher)
       HTM_TR_Begin (NULL);
 
       HTM_TD_Begin ("class=\"REC_C1_BOT RM\"");
-      fprintf (Gbl.F.Out,"<label for=\"%s\" class=\"%s\">",
-	       Dpt_PARAM_DPT_COD_NAME,ClassForm);
+      HTM_LABEL_Begin ("for=\"%s\" class=\"%s\"",Dpt_PARAM_DPT_COD_NAME,ClassForm);
       fprintf (Gbl.F.Out,"%s*:",Txt_Department);
       HTM_LABEL_End ();
       HTM_TD_End ();
@@ -4204,7 +4203,7 @@ static void Rec_ShowFormMyInsCtrDpt (bool IAmATeacher)
       HTM_TR_Begin (NULL);
 
       HTM_TD_Begin ("class=\"REC_C1_BOT RM\"");
-      fprintf (Gbl.F.Out,"<label for=\"Office\" class=\"%s\">",ClassForm);
+      HTM_LABEL_Begin ("for=\"Office\" class=\"%s\"",ClassForm);
       fprintf (Gbl.F.Out,"%s:",Txt_Office);
       HTM_LABEL_End ();
       HTM_TD_End ();
@@ -4227,7 +4226,7 @@ static void Rec_ShowFormMyInsCtrDpt (bool IAmATeacher)
       HTM_TR_Begin (NULL);
 
       HTM_TD_Begin ("class=\"REC_C1_BOT RM\"");
-      fprintf (Gbl.F.Out,"<label for=\"OfficePhone\" class=\"%s\">",ClassForm);
+      HTM_LABEL_Begin ("for=\"OfficePhone\" class=\"%s\"",ClassForm);
       fprintf (Gbl.F.Out,"%s:",Txt_Phone);
       HTM_LABEL_End ();
       HTM_TD_End ();
diff --git a/swad_search.c b/swad_search.c
index adcd157e2..81ffbb8e7 100644
--- a/swad_search.c
+++ b/swad_search.c
@@ -144,7 +144,7 @@ static void Sch_PutFormToSearchWithWhatToSearchAndScope (Act_Action_t Action,Hie
    /***** Scope (whole platform, current country, current institution,
                  current centre, current degree or current course) *****/
    HTM_DIV_Begin ("class=\"CM\"");
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:&nbsp;",Txt_Scope);
    Gbl.Scope.Allowed = 1 << Hie_SYS |
 	               1 << Hie_CTY |
@@ -162,7 +162,7 @@ static void Sch_PutFormToSearchWithWhatToSearchAndScope (Act_Action_t Action,Hie
    Sch_PutInputStringToSearch (NULL);
 
    /***** What to search? *****/
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out," %s&nbsp;",Txt_SEARCH_X_in_Y);
    fprintf (Gbl.F.Out,"<select name=\"WhatToSearch\" class=\"WHAT_TO_SEARCH\">");
    for (WhatToSearch = (Sch_WhatToSearch_t) 0;
diff --git a/swad_statistic.c b/swad_statistic.c
index 863ca2510..87c5189d9 100644
--- a/swad_statistic.c
+++ b/swad_statistic.c
@@ -419,7 +419,7 @@ void Sta_AskShowCrsHits (void)
          /* Selection of count type (number of pages generated, accesses per user, etc.) */
          Sta_WriteSelectorCountType ();
 
-         fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+         HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
          fprintf (Gbl.F.Out,"&nbsp;%s&nbsp;"
                             "<select id=\"GroupedBy\" name=\"GroupedBy\">",
                   Txt_distributed_by);
@@ -541,8 +541,7 @@ void Sta_AskShowGblHits (void)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"Role\" class=\"%s\">",
-            The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"Role\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Users);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -570,8 +569,7 @@ void Sta_AskShowGblHits (void)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"ScopeSta\" class=\"%s\">",
-            The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"ScopeSta\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Scope);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -594,8 +592,7 @@ void Sta_AskShowGblHits (void)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"CountType\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"CountType\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Show);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -604,7 +601,7 @@ void Sta_AskShowGblHits (void)
    Sta_WriteSelectorCountType ();
 
    /***** Type of statistic *****/
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"&nbsp;%s&nbsp;",Txt_distributed_by);
 
    if (Gbl.Stat.ClicksGroupedBy < Sta_CLICKS_GBL_PER_DAY ||
@@ -716,8 +713,7 @@ static void Sta_WriteSelectorAction (void)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"StatAct\" class=\"%s\">",
-            The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"StatAct\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Action);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -2079,7 +2075,7 @@ static void Sta_ShowDistrAccessesPerDayAndHour (unsigned long NumRows,MYSQL_RES
       Sta_PutHiddenParamScopeSta ();
      }
 
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:&nbsp;"
                       "<select name=\"ColorType\""
                       " onchange=\"document.getElementById('%s').submit();\">",
diff --git a/swad_survey.c b/swad_survey.c
index 7a4754acf..7b8315a82 100644
--- a/swad_survey.c
+++ b/swad_survey.c
@@ -1893,8 +1893,7 @@ void Svy_RequestCreatOrEditSvy (void)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"ScopeSvy\" class=\"%s\">",
-            The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"ScopeSvy\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Scope);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -1911,8 +1910,7 @@ void Svy_RequestCreatOrEditSvy (void)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"Title\" class=\"%s\">",
-	    The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"Title\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Title);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -1933,8 +1931,7 @@ void Svy_RequestCreatOrEditSvy (void)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RT\"");
-   fprintf (Gbl.F.Out,"<label for=\"Txt\" class=\"%s\">",
-            The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"Txt\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Description);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -2728,8 +2725,7 @@ static void Svy_ShowFormEditOneQst (long SvyCod,struct SurveyQuestion *SvyQst,
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RT\"");
-   fprintf (Gbl.F.Out,"<label for=\"Txt\" class=\"%s\">",
-            The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"Txt\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Wording);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -2784,8 +2780,8 @@ static void Svy_ShowFormEditOneQst (long SvyCod,struct SurveyQuestion *SvyQst,
 
       /* Label with the number of the answer */
       HTM_TD_Begin ("class=\"RT\"");
-      fprintf (Gbl.F.Out,"<label for=\"AnsStr%u\" class=\"%s\">",
-               NumAns,The_ClassFormInBox[Gbl.Prefs.Theme]);
+      HTM_LABEL_Begin ("for=\"AnsStr%u\" class=\"%s\">",
+                       NumAns,The_ClassFormInBox[Gbl.Prefs.Theme]);
       fprintf (Gbl.F.Out,"%u)",NumAns + 1);
       HTM_LABEL_End ();
       HTM_TD_End ();
@@ -3469,16 +3465,16 @@ static void Svy_WriteAnswersOfAQst (struct Survey *Svy,
 
 	 /* Write the number of option */
 	 HTM_TD_Begin ("class=\"SVY_OPT LT\"");
-	 fprintf (Gbl.F.Out,"<label for=\"Ans%010u_%010u\" class=\"DAT\">",
-		  (unsigned) SvyQst->QstCod,NumAns);
+	 HTM_LABEL_Begin ("for=\"Ans%010u_%010u\" class=\"DAT\"",
+		          (unsigned) SvyQst->QstCod,NumAns);
 	 fprintf (Gbl.F.Out,"%u)",NumAns + 1);
 	 HTM_LABEL_End ();
 	 HTM_TD_End ();
 
 	 /* Write the text of the answer */
 	 HTM_TD_Begin ("class=\"LT\"");
-	 fprintf (Gbl.F.Out,"<label for=\"Ans%010u_%010u\" class=\"DAT\">",
-		  (unsigned) SvyQst->QstCod,NumAns);
+	 HTM_LABEL_Begin ("for=\"Ans%010u_%010u\" class=\"DAT\"",
+		          (unsigned) SvyQst->QstCod,NumAns);
 	 fprintf (Gbl.F.Out,"%s",SvyQst->AnsChoice[NumAns].Text);
 	 HTM_LABEL_End ();
 	 HTM_TD_End ();
diff --git a/swad_test.c b/swad_test.c
index ea57a1ee6..48e4c75a9 100644
--- a/swad_test.c
+++ b/swad_test.c
@@ -354,8 +354,7 @@ void Tst_ShowFormAskTst (void)
          HTM_TR_Begin (NULL);
 
          HTM_TD_Begin ("class=\"RM\"");
-         fprintf (Gbl.F.Out,"<label for=\"NumQst\" class=\"%s\">",
-                  The_ClassFormInBox[Gbl.Prefs.Theme]);
+         HTM_LABEL_Begin ("for=\"NumQst\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
          fprintf (Gbl.F.Out,"%s:",Txt_No_of_questions);
          HTM_LABEL_End ();
          HTM_TD_End ();
@@ -472,8 +471,7 @@ void Tst_ShowNewTest (void)
 
 	    /***** Test result will be saved? *****/
 	    HTM_DIV_Begin ("class=\"CM\"");
-	    fprintf (Gbl.F.Out,"<label class=\"%s\">",
-		     The_ClassFormInBox[Gbl.Prefs.Theme]);
+	    HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
 	    fprintf (Gbl.F.Out,"<input type=\"checkbox\" name=\"Save\" value=\"Y\"");
 	    if (Gbl.Test.AllowTeachers)
 	       fprintf (Gbl.F.Out," checked=\"checked\"");
@@ -1138,7 +1136,7 @@ static void Tst_PutFormToEditQstMedia (struct Media *Media,int NumMediaInForm,
       HTM_DIV_Begin ("class=\"TEST_MED_EDIT_FORM\"");
 
       /***** Choice 1: No media *****/
-      fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+      HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
       fprintf (Gbl.F.Out,"<input type=\"radio\" name=\"%s\" value=\"%u\"",
 	       ParamUploadMedia.Action,Med_ACTION_NO_MEDIA);
       if (OptionsDisabled)
@@ -1150,7 +1148,7 @@ static void Tst_PutFormToEditQstMedia (struct Media *Media,int NumMediaInForm,
       fprintf (Gbl.F.Out,"<br />");
 
       /***** Choice 2: Current media *****/
-      fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+      HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
       fprintf (Gbl.F.Out,"<input type=\"radio\" name=\"%s\" value=\"%u\""
 	                 " checked=\"checked\"",
 	       ParamUploadMedia.Action,Med_ACTION_KEEP_MEDIA);
@@ -1166,7 +1164,7 @@ static void Tst_PutFormToEditQstMedia (struct Media *Media,int NumMediaInForm,
 
       /***** Choice 3: Change media *****/
       UniqueId++;
-      fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+      HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
       fprintf (Gbl.F.Out,"<input type=\"radio\" id=\"chg_img_%u\" name=\"%s\""
 			 " value=\"%u\"",
 	       UniqueId,ParamUploadMedia.Action,
@@ -1708,7 +1706,7 @@ static void Tst_ShowFormSelTags (unsigned long NumRows,MYSQL_RES *mysql_res,
       HTM_TD_Empty (1);
 
    HTM_TD_Begin ("class=\"LM\"");
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"<input type=\"checkbox\" name=\"AllTags\" value=\"Y\"");
    if (Gbl.Test.Tags.All)
       fprintf (Gbl.F.Out," checked=\"checked\"");
@@ -1742,7 +1740,7 @@ static void Tst_ShowFormSelTags (unsigned long NumRows,MYSQL_RES *mysql_res,
         }
 
       HTM_TD_Begin ("class=\"LM\"");
-      fprintf (Gbl.F.Out,"<label class=\"DAT\">");
+      HTM_LABEL_Begin ("class=\"DAT\"");
       fprintf (Gbl.F.Out,"<input type=\"checkbox\" name=\"ChkTag\" value=\"%s\"",
 	       row[1]);
       if (Gbl.Test.Tags.List)
@@ -1919,7 +1917,7 @@ static void Tst_ShowFormConfigTst (void)
 	Pluggable <= Tst_PLUGGABLE_YES;
 	Pluggable++)
      {
-      fprintf (Gbl.F.Out,"<label class=\"DAT\">");
+      HTM_LABEL_Begin ("class=\"DAT\"");
       fprintf (Gbl.F.Out,"<input type=\"radio\" name=\"Pluggable\" value=\"%u\"",
 	       (unsigned) Pluggable);
       if (Pluggable == Gbl.Test.Config.Pluggable)
@@ -1958,8 +1956,8 @@ static void Tst_ShowFormConfigTst (void)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RT\"");
-   fprintf (Gbl.F.Out,"<label for=\"MinTimeNxtTstPerQst\" class=\"%s\">",
-            The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"MinTimeNxtTstPerQst\" class=\"%s\"",
+                    The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Minimum_time_seconds_per_question_between_two_tests);
     HTM_LABEL_End ();
    HTM_TD_End ();
@@ -1986,7 +1984,7 @@ static void Tst_ShowFormConfigTst (void)
 	Feedback < Tst_NUM_TYPES_FEEDBACK;
 	Feedback++)
      {
-      fprintf (Gbl.F.Out,"<label class=\"DAT\">");
+      HTM_LABEL_Begin ("class=\"DAT\"");
       fprintf (Gbl.F.Out,"<input type=\"radio\" name=\"Feedback\" value=\"%u\"",
 	       (unsigned) Feedback);
       if (Feedback == Gbl.Test.Config.Feedback)
@@ -2022,7 +2020,7 @@ static void Tst_PutInputFieldNumQst (const char *Field,const char *Label,
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RM\"");
-   fprintf (Gbl.F.Out,"<label for=\"%s\" class=\"DAT\">",Field);
+   HTM_LABEL_Begin ("for=\"%s\" class=\"DAT\"",Field);
    fprintf (Gbl.F.Out,"%s",Label);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -2338,7 +2336,7 @@ static void Tst_ShowFormAnswerTypes (unsigned NumCols)
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"LM\"");
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"<input type=\"checkbox\" name=\"AllAnsTypes\" value=\"Y\"");
    if (Gbl.Test.AllAnsTypes)
       fprintf (Gbl.F.Out," checked=\"checked\"");
@@ -2358,7 +2356,7 @@ static void Tst_ShowFormAnswerTypes (unsigned NumCols)
       HTM_TR_Begin (NULL);
 
       HTM_TD_Begin ("class=\"LM\"");
-      fprintf (Gbl.F.Out,"<label class=\"DAT\">");
+      HTM_LABEL_Begin ("class=\"DAT\"");
       fprintf (Gbl.F.Out,"<input type=\"checkbox\" name=\"AnswerType\" value=\"%u\"",
                (unsigned) AnsType);
       Ptr = Gbl.Test.ListAnsTypes;
@@ -3734,16 +3732,14 @@ static void Tst_WriteChoiceAnsViewTest (unsigned NumQst,long QstCod,bool Shuffle
       HTM_TD_End ();
 
       HTM_TD_Begin ("class=\"LT\"");
-      fprintf (Gbl.F.Out,"<label for=\"Ans%06u_%u\" class=\"ANS_TXT\">",
-	       NumQst,NumOpt);
+      HTM_LABEL_Begin ("for=\"Ans%06u_%u\" class=\"ANS_TXT\"",NumQst,NumOpt);
       fprintf (Gbl.F.Out,"%c)&nbsp;",'a' + (char) NumOpt);
       HTM_LABEL_End ();
       HTM_TD_End ();
 
       /***** Write the option text *****/
       HTM_TD_Begin ("class=\"LT\"");
-      fprintf (Gbl.F.Out,"<label for=\"Ans%06u_%u\" class=\"ANS_TXT\">",
-               NumQst,NumOpt);
+      HTM_LABEL_Begin ("for=\"Ans%06u_%u\" class=\"ANS_TXT\"",NumQst,NumOpt);
       fprintf (Gbl.F.Out,"%s",Gbl.Test.Answer.Options[NumOpt].Text);
       HTM_LABEL_End ();
       Med_ShowMedia (&Gbl.Test.Answer.Options[NumOpt].Media,
@@ -4187,7 +4183,7 @@ void Tst_WriteChoiceAnsViewMatch (long MchCod,unsigned QstInd,long QstCod,
 
       /***** Write the option text and the result *****/
       HTM_TD_Begin ("class=\"LT\"");
-      fprintf (Gbl.F.Out,"<label for=\"Ans%06u_%u\" class=\"%s\">",QstInd,NumOpt,Class);
+      HTM_LABEL_Begin ("for=\"Ans%06u_%u\" class=\"%s\"",QstInd,NumOpt,Class);
       fprintf (Gbl.F.Out,"%s",Gbl.Test.Answer.Options[Indexes[NumOpt]].Text);
       HTM_LABEL_End ();
       Med_ShowMedia (&Gbl.Test.Answer.Options[Indexes[NumOpt]].Media,
@@ -5144,8 +5140,7 @@ static void Tst_PutFormEditOneQst (char Stem[Cns_MAX_BYTES_TEXT + 1],
    HTM_TR_Begin (NULL);
 
    HTM_TD_Begin ("class=\"RT\"");
-   fprintf (Gbl.F.Out,"<label for=\"Stem\" class=\"%s\">",
-            The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("for=\"Stem\" class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:",Txt_Wording);
    HTM_LABEL_End ();
    HTM_TD_End ();
@@ -5160,7 +5155,7 @@ static void Tst_PutFormEditOneQst (char Stem[Cns_MAX_BYTES_TEXT + 1],
                               false);
 
    /***** Feedback *****/
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s (%s):<br />",Txt_Feedback,Txt_optional);
    HTM_TEXTAREA_Begin ("name=\"Feedback\" class=\"STEM_TEXTAREA\" rows=\"2\"");
    if (Feedback)
@@ -5208,7 +5203,7 @@ static void Tst_PutFormEditOneQst (char Stem[Cns_MAX_BYTES_TEXT + 1],
    HTM_TD_End ();
 
    HTM_TD_Begin ("class=\"LT\"");
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:&nbsp;"
                       "<input type=\"text\" name=\"AnsInt\""
                       " size=\"11\" maxlength=\"11\" value=\"%ld\"",
@@ -5248,7 +5243,7 @@ static void Tst_PutFormEditOneQst (char Stem[Cns_MAX_BYTES_TEXT + 1],
    HTM_TD_Empty (1);
 
    HTM_TD_Begin ("class=\"LT\"");
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"<input type=\"checkbox\" name=\"Shuffle\" value=\"Y\"");
    if (Gbl.Test.Shuffle)
       fprintf (Gbl.F.Out," checked=\"checked\"");
@@ -5367,7 +5362,7 @@ static void Tst_PutFormEditOneQst (char Stem[Cns_MAX_BYTES_TEXT + 1],
                                  OptionsDisabled);
 
       /* Feedback */
-      fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+      HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
       fprintf (Gbl.F.Out,"%s (%s):<br />",Txt_Feedback,Txt_optional);
       HTM_TEXTAREA_Begin ("name=\"FbStr%u\" class=\"ANSWER_TEXTAREA\" rows=\"2\"%s",
 			  NumOpt,OptionsDisabled ? " disabled=\"disabled\"" :
@@ -5413,7 +5408,7 @@ static void Tst_PutFloatInputField (const char *Label,const char *Field,
   {
    extern const char *The_ClassFormInBox[The_NUM_THEMES];
 
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s&nbsp;"
                       "<input type=\"text\" name=\"%s\""
                       " size=\"11\" maxlength=\"%u\""
@@ -5435,7 +5430,7 @@ static void Tst_PutTFInputField (const char *Label,char Value)
   {
    extern const char *The_ClassFormInBox[The_NUM_THEMES];
 
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"<input type=\"radio\" name=\"AnsTF\" value=\"%c\"",Value);
    if (Gbl.Test.Answer.TF == Value)
       fprintf (Gbl.F.Out," checked=\"checked\"");
diff --git a/swad_test_import.c b/swad_test_import.c
index 38bc07ad9..ba8a541c2 100644
--- a/swad_test_import.c
+++ b/swad_test_import.c
@@ -141,7 +141,7 @@ void TsI_ShowFormImportQstsFromXML (void)
 
    /***** Write a form to import questions *****/
    Frm_StartForm (ActImpTstQst);
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:&nbsp;"
                       "<input type=\"file\" name=\"%s\" accept=\".xml\""
                       " onchange=\"document.getElementById('%s').submit();\" />",
diff --git a/swad_timetable.c b/swad_timetable.c
index 478e4ea91..c2edbd01f 100644
--- a/swad_timetable.c
+++ b/swad_timetable.c
@@ -1662,7 +1662,7 @@ static void TT_TimeTableDrawCell (unsigned Weekday,unsigned Interval,unsigned Co
 	      {
 	       /***** Group *****/
 	       fprintf (Gbl.F.Out,"<br />");
-	       fprintf (Gbl.F.Out,"<label for=\"TTGrp%s\">",CellStr);
+	       HTM_LABEL_Begin ("for=\"TTGrp%s\"",CellStr);
 	       fprintf (Gbl.F.Out,"%s",Txt_Group);
 	       HTM_LABEL_End ();
 	       fprintf (Gbl.F.Out,"<select id=\"TTGrp%s\" name=\"TTGrp\""
@@ -1702,7 +1702,7 @@ static void TT_TimeTableDrawCell (unsigned Weekday,unsigned Interval,unsigned Co
 
 	       /***** Info *****/
 	       fprintf (Gbl.F.Out,"<br />");
-	       fprintf (Gbl.F.Out,"<label for=\"TTInf%s\">",CellStr);
+	       HTM_LABEL_Begin ("for=\"TTInf%s\"",CellStr);
 	       fprintf (Gbl.F.Out,"%s",Txt_Info);
 	       HTM_LABEL_End ();
 	       fprintf (Gbl.F.Out,"<input id=\"TTInf%s\" name=\"TTInf\""
@@ -1719,8 +1719,7 @@ static void TT_TimeTableDrawCell (unsigned Weekday,unsigned Interval,unsigned Co
 	      {
 	       /***** Info *****/
 	       fprintf (Gbl.F.Out,"<br />");
-	       fprintf (Gbl.F.Out,"<label for=\"TTInf%s\" class=\"DAT_SMALL\">",
-			CellStr);
+	       HTM_LABEL_Begin ("for=\"TTInf%s\" class=\"DAT_SMALL\"",CellStr);
 	       fprintf (Gbl.F.Out,"%s",Txt_Info);
 	       HTM_LABEL_End ();
                fprintf (Gbl.F.Out,"<input id=\"TTInf%s\" name=\"TTInf\""
diff --git a/swad_user.c b/swad_user.c
index 333e91f27..344cd0fb7 100644
--- a/swad_user.c
+++ b/swad_user.c
@@ -2607,7 +2607,7 @@ void Usr_WriteFormLogin (Act_Action_t NextAction,void (*FuncParams) (void))
 
    /***** User's ID/nickname *****/
    HTM_DIV_Begin ("class=\"LM\"");
-   fprintf (Gbl.F.Out,"<label for=\"UsrId\">");
+   HTM_LABEL_Begin ("for=\"UsrId\"");
    Ico_PutIcon ("user.svg",Txt_User[Usr_SEX_UNKNOWN],"CONTEXT_ICO_16x16");
    HTM_LABEL_End ();
    fprintf (Gbl.F.Out,"<input type=\"text\" id=\"UsrId\" name=\"UsrId\""
@@ -2621,7 +2621,7 @@ void Usr_WriteFormLogin (Act_Action_t NextAction,void (*FuncParams) (void))
 
    /***** User's password *****/
    HTM_DIV_Begin ("class=\"LM\"");
-   fprintf (Gbl.F.Out,"<label for=\"UsrPwd\">");
+   HTM_LABEL_Begin ("for=\"UsrPwd\"");
    Ico_PutIcon ("key.svg",Txt_Password,"CONTEXT_ICO_16x16");
    HTM_LABEL_End ();
    fprintf (Gbl.F.Out,"<input type=\"password\" id=\"UsrPwd\" name=\"UsrPwd\""
@@ -3507,7 +3507,7 @@ void Usr_ShowFormsLogoutAndRole (void)
                Txt_ROLES_SINGUL_Abc[Gbl.Usrs.Me.Role.Logged][Gbl.Usrs.Me.UsrDat.Sex]);
    else
      {
-      fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+      HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
       fprintf (Gbl.F.Out,"%s:&nbsp;",Txt_Role);
       Rol_PutFormToChangeMyRole (NULL);
       HTM_LABEL_End ();
@@ -6398,7 +6398,7 @@ static void Usr_PutCheckboxListWithPhotos (void)
    Par_PutHiddenParamChar ("WithPhotosExists",'Y');
 
    /***** Put checkbox to select whether list users with photos *****/
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"<input type=\"checkbox\" name=\"WithPhotos\""
 	              " value=\"Y\"");
    if (Gbl.Usrs.Listing.WithPhotos)
@@ -7327,7 +7327,7 @@ void Usr_ListDataAdms (void)
    HTM_DIV_Begin ("class=\"CM\"");
    Frm_StartForm (ActLstOth);
    Usr_PutParamListWithPhotos ();
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:&nbsp;",Txt_Scope);
    Sco_PutSelectorScope ("ScopeUsr",true);
    HTM_LABEL_End ();
@@ -7794,7 +7794,7 @@ void Usr_SeeGuests (void)
       HTM_DIV_Begin ("class=\"CM\"");
       Frm_StartForm (ActLstGst);
       Usr_PutParamsPrefsAboutUsrList ();
-      fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+      HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
       fprintf (Gbl.F.Out,"%s:&nbsp;",Txt_Scope);
       Sco_PutSelectorScope ("ScopeUsr",true);
       HTM_LABEL_End ();
@@ -7939,7 +7939,7 @@ void Usr_SeeStudents (void)
 	 HTM_DIV_Begin ("class=\"CM\"");
 	 Frm_StartForm (ActLstStd);
 	 Usr_PutParamsPrefsAboutUsrList ();
-	 fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+	 HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
 	 fprintf (Gbl.F.Out,"%s:&nbsp;",Txt_Scope);
 	 Sco_PutSelectorScope ("ScopeUsr",true);
 	 HTM_LABEL_End ();
@@ -8112,7 +8112,7 @@ void Usr_SeeTeachers (void)
    HTM_DIV_Begin ("class=\"CM\"");
    Frm_StartForm (ActLstTch);
    Usr_PutParamsPrefsAboutUsrList ();
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"%s:&nbsp;",Txt_Scope);
    Sco_PutSelectorScope ("ScopeUsr",true);
    HTM_LABEL_End ();
@@ -8355,7 +8355,7 @@ static void Usr_ShowOneListUsrsOption (Usr_ListUsrsOption_t ListUsrsAction,
    if (ListUsrsAction == Gbl.Usrs.Selected.Option)
       fprintf (Gbl.F.Out," checked=\"checked\"");
    fprintf (Gbl.F.Out," />");
-   fprintf (Gbl.F.Out,"<label for=\"ListUsrsAction%u\">",(unsigned) ListUsrsAction);
+   HTM_LABEL_Begin ("for=\"ListUsrsAction%u\"",(unsigned) ListUsrsAction);
    fprintf (Gbl.F.Out,"%s",Label);
    HTM_LABEL_End ();
 
@@ -8954,9 +8954,10 @@ void Usr_PutSelectorNumColsClassPhoto (void)
    unsigned Cols;
 
    /***** Start selector *****/
-   fprintf (Gbl.F.Out,"<label class=\"%s\">",The_ClassFormInBox[Gbl.Prefs.Theme]);
+   HTM_LABEL_Begin ("class=\"%s\"",The_ClassFormInBox[Gbl.Prefs.Theme]);
    fprintf (Gbl.F.Out,"<select name=\"ColsClassPhoto\""
-                      " onchange=\"document.getElementById('%s').submit();\">",Gbl.Form.Id);
+                      " onchange=\"document.getElementById('%s').submit();\">",
+	    Gbl.Form.Id);
 
    /***** Put a row in selector for every number from 1 to Usr_CLASS_PHOTO_COLS_MAX *****/
    for (Cols = 1;