5. The tree is very tall.(改为感叹句，How~)

4. There is something wrong with my watch.(改为否定句)

2. She used to wear white skirt.(改为否定句)

3 I think Jack is a good student.(改为否定句)

1. Lucy has finished the work.(改为一般疑问句)

20. -Do you know　　 ? 　　 -Yes. He is a teacher.

　 A, whom he is　　 B. whom is he　　 C. what is he　　 D. what he is

19. It　　 ten years since I taught in the school.

　 A. will　　　 B. was　 　　C. has　　　 D. is

18. Do you know　　 ?

　 A. what are you listening　　　　 B. what you are listening

　 C. what you are listening to　　 D. what are you listening to

17. You may　　 do it yourself　　 leave it to me.

　 A. either…or　　 B. neither…nor　 　　C. whether…or　　　 D. both…and

16. This is the place　　 I have ever visited.

　 A. there　　　 B. when　　　 C. where　　　 D. which

15. There are heavy clouds in the sky　　 it is going to rain.

　 A. if　　　 B. that　　　 C. as if　　　 D. whether