If both sailboats have furled white sails.
return sailboats ;return sails of  #1 ;return #1 where #2 are  furled ;return #1 where #2 are  white ;return #1 in  both  #3 and #4 ;return number of #5 ;return if  #6 is  equal to two
['select', 'project', 'comparative', 'comparative', 'intersection', 'aggregate', 'boolean']