3. --　　 　I hand in the paper on Monday?

　 　-- No, you don’t have to.

　　 A. Do　 B. Must　 C. Need　 D. May

2. You 　　　　listen to the teacher carefully in class.

　　 A. have to　 B. must　 C. need　 D. may

1. There is no bus today. I’m afraid you 　　　walk home.

A. can　　 B. may　　 C. be able to　 D. have to

8. It’s a great pity that I missed Professor Hu’s excellent lecture yesterday.

7. The professor walked here and there, thinking about a difficult problem.

6. If you want to be successful, you should depend on yourself.

5. Most boys are keen on playing football.

4. Some people think computers are cleverer than human beings at present.

3. We started at five in the morning to catch the earliest flight.

2. Mr. Smith had an awful day at the office that day.