According to the traffic rules, you _________ wear the safe belt while you are driving.

No student       go out of school for snacks during the break without the teacher’s permission.

-- _____ I ask you a question, Mr. Wang?      -- Yes, you _______.

—Look! A book is on the floor. Whose is it?—It ______ be Rick’s. It has his name on it.

－What do you think we can do for our aged parents?－You_______ do anything except to be with them and be yourself.