If some zebras are in water.
return zebras ;return water ;return #1 that are in  #2 ;return number of  #1 ;return number of  #3 ;return difference of #4 and #5 ;return if  #5 is at least one ;return if  #6 is at least one ;return if  both  #7 and #8 are true
['select', 'select', 'filter', 'aggregate', 'aggregate', 'arithmetic', 'boolean', 'boolean', 'boolean']