20.They _____ on the program for almost one week before I joined them, and now we _____ on it as no god results have come out so far.

　 A. had been working; are still working　　　 B. had worked; were still working

　 C. have been working; have worked　　　　 D. have worked; are still working

19.--Hi, Tracy; how are you doing?

--I’m tired out, for I ______my living room all day.

A．painted　　　　　　　　　　　 　B．had painted

C．have painted　　　　　　　 　D．have been painting

18.On returning home , I found I ______ umbrella in the office. A had left　　　　　　　　　　　 B. have left

C. left　　　　　　　　　　　　　 　D. would leave　

17.He said that his bike __________stolen and he __________have to telephone the police.

A. was; would　　　　　　　　　　 B. has; will

C. has been; will　　　　　　　　　 D. had been; would

16.　The train _____ because of an accident; many passengers are now waiting anxiously at the railway station.

　 A. has been delayed　　　　　　　　　　 B. delayed　　　　

　 C. has delayed　　　　　　　　　　　 　　 D. had been delayed

15.Finding out more about the destination you ____________ chosen ____________ not only a good way to save money and avoid problems.

A. are; is　　　　　　　　　　　　　 B. are; are　　　　　　　　 C. have; is 　　　　　　　 D. have; are

14.The old worker has been fired and now a young man ______.

A. took place　　　　 　　　　B. has taken the place

C. takes place of him　 　　　　D. has taken his place

13.He promised us that he _______ early but he _______yet.

A would be; hasn't arrived　　　　　　　　　　　　　　　　　　　　　 B. is ; hasn't been arriving

C. should be ; isn't arriving　 　　　　　　　　　　　　　　　　　　　　 D will be ; hadn't arrived　

12.-- What were you doing when Ton phoned you?

-- I had just finished my work and ____ to take a shower.

　 A. had started　　　 B. started　　　　　 C. have started　 　D. was starting

11.Shirley _____ a book about China last year but I don’t know whether she has finished it.

　 A. has written　　　 B. wrote　　　　　 C. had written　　 D. was writing