22. Everyone ___ do his best for the modernizations lf our country.

　 A can　　　 B may　　　　 C should　　　 　D might

21. One ought ____ for what one hasn’t done.

　 A not to be punished　 B to not be punished　　 C to not punish　　 D not be punished

20. Mary was not in her bedroom yesterday afternoon. She ___　 in her classroom.

　 A should have been　　 B must have been　　　 C must be　　 　D should be

19. The room is in a terrible mess; it ____ cleaned.

　 A can’t have been　　　 B shouldn’t have been　　

C mustn’t have been　　 D wouldn’t have been

18. John’s score on the test is the highest in the class; he ___ last night.

　 A should study　　 B should have studied　　 C must have studied　　 D must have to study

17. You must have known the result, ____ you?

　 A mustn’t　　　 B can’t　　　　 C haven’t　　　　 D don’t

16. You must be joking, _____ you?

　 A mustn’t　　　 B needn’t　　　　 C can’t　　　　 D aren’t

15. My watch doesn’t work now. There ____ be something wrong with it.

　 A may　　　 B can　　　 C could　　　 D must

14. ---Look, it ___ be Professor Wang.

　 ---No, it ____ be him, as he has gone abroad.

　 A may; mustn’t　　　 B must; may not　　　 C must; can’t　　　 D can; may not

13. You ____ walk for miles and miles in the hills without meeting anyone in the daytime.

　 A must　　 B need　　　 C may　　　　 D can