query: SELECT DISTINCT T2.lastname FROM list AS T1 JOIN teachers AS T2 ON T1.classroom  =  T2.classroom WHERE grade  =  5
question: what are the last names of the teachers who teach grade 5?
query_toks: SELECT DISTINCT T2.lastname FROM list AS T1 JOIN teachers AS T2 ON T1.classroom = T2.classroom WHERE grade = 5
query_toks_no_value: select distinct t2 . lastname from list as t1 join teachers as t2 on t1 . classroom = t2 . classroom where grade = value
question_toks: what are the last names of the teachers who teach grade 5?