Exercise 3. Supply should/ought to/must/need or have to in the correct tense and form. Put the infinitive into the appropriate form. 1. We ... (to leave) at 11 o'clock last night because the last bus went at 11:20.
2. I don't think you ... (to offer) to help him. You've got enough work to do yourself.
3. They ... (not to pay) to stay in a hotel. They can stay with us.
4. You ... (to come round) for dinner one evening. We haven't had a good talk for a long time.
5. We ... (to run) all the way to the station because we were late for the train.
6. It's your own fault that you are so tired. You ... (not to go) to bed so late.
7. Hurry up! You ... (not to have) a bath now. The taxi is coming in 20 minutes.
8. You ... (not to allow) David to walk home from school every day on his own. He's too young.
9. You ... (not to tell) him what happened. He would never forgive us.
10. You ... (to go) to that new French restaurant in town. It's the best restaurant I've ever been to.
11. Paul ... (not to get up) early in the morning but everyone else in the house does.
12. If I fail any of my exams, I... (to take) all of them in November.
13. The wedding has been cancelled so I (not to buy)that new suit. It was a waste of money.
14. I ... (to take) the children to school every morning before I go to the university.
15. You (not to eat) in the lecture halls: it's against the college regulations.
16. The letter ... (to be hidden) where no one will ever find it. Its contents ... (to remain) a secret for ever.
17. ... you (to wear) a uniform at work?
18. Please don't say anymore. I already know the truth so you ... (not to lie) to me.
19. We ... (not to get up) early this morning because we had no lectures.
20. Passengers ... (to fasten) their seat belts.