Fix bug.

app/helpers/admin/seminars_field_helper.rb

@@ -448,7 +448,7 @@ protected
       plc = typeD["placeholder"][I18n.locale].to_s.blank? ? nil : "(#{typeD["placeholder"][I18n.locale]})"
       label_tag(key, '' , :class=>"col-sm-2 control-label muted") do
         concat (!@require.blank? ? '*'+title : title)
-        if nil
+        if plc
           concat tag(:br)
           concat plc
         end