21.--- Mike , what new course are you going to have in ______ second grade?
-- I’m going to learn ______second foreign language.
A. a; the B. the; a C. the; / D./; a
22.--- I think Jane is at home.
--- No, she _______be at home, for she phoned me from the airport just ten minutes ago.
A. mustn’t B. needn’t C. can’t D. might not
