If a dog is standing on all fours on something made of cement.
return dog ;return cement ;return something made of  #2 ;return #1 that is  standing on all fours ;return #4 that is  on #3 ;return number of #5 ;return If #6 is  at least one
['select', 'select', 'project', 'filter', 'filter', 'aggregate', 'boolean']