CREATE TABLE list (lastname CLOB, firstname CLOB, grade NUMBER, classroom NUMBER)
CREATE TABLE teachers (lastname CLOB, firstname CLOB, classroom NUMBER)

What are the last names of the teachers who teach the student called GELL TAMI?
SELECT T2.lastname FROM list AS T1 JOIN teachers AS T2 ON T1.classroom = T2.classroom WHERE T1.firstname = "GELL" AND T1.lastname = "TAMI"
SELECT "T2"."lastname" FROM "list" "T1" JOIN "teachers" "T2" ON "T1"."classroom" = "T2"."classroom" WHERE "GELL" = "T1"."firstname" AND "T1"."lastname" = "TAMI"