If at least one beatle has its hind legs on a ball while its front legs are on the ground.
return beatles ;return hind legs  of #1 ;return front legs  of #1 ;return ball ;return #1 where  #2 are on #4 ;return the  ground ;return #1 where  #3 are on #6 ;return #1 in  both  #5 and #7 ;return number of  #8 ;return if  #9 is at least one
['select', 'project', 'project', 'select', 'comparative', 'select', 'comparative', 'intersection', 'aggregate', 'boolean']