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

If you won’t do as I told you, you____ not go to the party.

---Look. The man at the gate _____ be our headmaster. He is always standing there every morning.---No. it ____ be him. He is having a meeting in the office now.

It’s nothing serious. You’ve just caught.          a cold. 

The number of teachers in our school _______ greatly increased last term.A number of teachers in this school ______from the countryside.