If there are at least 4 black ox in the water that is landlocked by grass.
return ox ;return #1 that are black ;return water ;return grass ;return #3 that is landlocked by #4 ;return #2 in  #5 ;return the  number of  #6 ;return if  #7 is at least 4
['select', 'filter', 'select', 'select', 'filter', 'filter', 'aggregate', 'boolean']