query: SELECT avg(age) FROM visitor WHERE Level_of_membership  <=  4
question: What-all is the average age of the visitors that's membership ain't more higher than 4?
query_toks: SELECT avg ( age ) FROM visitor WHERE Level_of_membership < = 4
query_toks_no_value: select avg ( age ) from visitor where level_of_membership < = value
question_toks: What-all is the average age of the visitors that's membership ain't more higher than 4?