What are the party emails associated with parties that used the party form that is the most common?
return parties ;return forms of #1 ;return number of  #1 for each #2 ;return #2 where #3 is  the   highest ;return #1 where #2 is  #4 ;return the   party emails of #5
['select', 'project', 'group', 'comparative', 'comparative', 'project']