If two zebras facing the same way are grazing in the grass.
return zebras ;return the  grass ;return #1 grazing in  #2 ;return way facing of #3 ;return #3 where  #4 is the  same ;return number of  #5 ;return if  #6 is equal to  two
['select', 'select', 'filter', 'project', 'comparative', 'aggregate', 'boolean']