1. A 　2. A 　3. B 　4. B 　5. A 　6. C 　7. A 　8. C 9. D 10. B 11. A 　12. B 　13. A 　14. B 　15. C 　16. B 17. A 　l8. A 　19. B 　20. B

解析：

20. It is reported that ________ mountain lion is in ________ danger of dying out.

A. a, /　　 B. the, /　　 C. a, the　　 D. the. a

Key:

19. How nice to go out for some fresh air ________ a cool summer night!

A. in　　 B. on　　　 C. at　　　 D. during

18. Don’t be discouraged, h won’t be long ________ you catch up with the others.

A. before　　 B. after　 C. when　　 D. that

17. The light ____, so he had to lie down to rest.

A. went out　 　　B. went off

C. turned out　 　D. shut out

16. I would rather you _____ to see him at once.

A. go　　 B. went　 C. to go　　 D. going

15. Our headmaster won’t ______our doing such things.

A. let　　 B. promise　 C. permit　 D. allowed

14. -I’m sorry for being late. Thank you for waiting so long.

-________.

A. With pleasure　　　　 B. That’s all right

C. It doesn’t matter　　　 D. No problems

13. If it is not yours, then ________ can it be.’?

A. who else’s　　　　　 B. who’s else

C. what else　　　　　 D. which dsc

12. The sun ________, everything is coming back to life.

A. rised　　 B. risen　　 C. raising　　 D. rose