18. They ______day and night.

　 A. are made work B. are made to work

　 C. made to be worked 　　　　　　　　　　　　　 D. are making to work

17. We can't enter the room because its door______ .

　 A. locked 　　　　　　　 B. locks 　　　　　　　　 C. is locked 　　　　　 D. is locking

16. When water______ , it will be changed into vapor(蒸汽).

　 A. is heated 　　　　　 B. heating 　　　　　　　 C. has heated 　　　　 D. heats

15. The war______ in 1941.

　 A. broke out 　　　　　 B. had been broken out

　 C. was broken out D. had broken out

14. I ______the way to the railway station by a policeman.

　 A. was shown 　　　 B. showed 　　　　　　 C. have shown 　　　 D. was showing

13. We can't use the bridge now, because it______ .

　 A. has been repaired 　　　　　　　　　　　　　　 B. is repairing 　　　　 C. is repaired 　　　 D. is being repaired

12. The picture______　 in October, 1996.

　 A. was taking 　　　　 B. had been taken C. was taken 　　　　 D. had taken

11. Great changes ____ place. Many new schools____　 .

　 A. have taken, have been opened 　　　　 B. take, are open

　 C. are taken, open 　　　　　　　　　　　　　　　　 D. have been taken, are opened

10. He ____ by the teachers.

　 A. is always praised 　　　　　　　　　　　　　　　 B. praises

　 C. have been praised 　　　　　　　　　　　　　　 D. always is praised

9. Rice ___ also _____ in their hometown.

　 A. is…grown 　　　　 B. is…grew 　　　　　 C. was…grew 　　　 D. was…grown