_________ many times, he finally understood it.

A. Having told       B. Having been told         C. Told             D. Telling

A tiger is ___animal that feeds on animals.

A. an eating-meat      B. a meat-eating     C. an eat-meat         D. a meat-eaten

A survey _______ in 2002 by the Computer Security Institute, a private organization in the USA, showed that 90 percent of the 503 biggest companies and government departments questioned _______ their security systems _______ into in the previous year.

A. conducted ; had ; broke                      B. conducted; had had ; broken

C. was conducted ; had had ; broken       D. to be conducted; had ; broke

       as it was at such a time, his work attracted much attention.

   A. Being published   B. Publishing       C. Published        D. To be published

 With ticket prices rising, TV        over as the typical way of watching a game for the young and old.

A. has taken     B. had taken         C. was taken          D. is taken

— We didn't find Smith attending the lecture.

— No one _____ him about ______ a lecture the following day.

A. told; there to be                   B. had told, there to be

C. told; there was                    D. had told, there being

—I wish I had succeeded in the completion.

—Yeah. I know. But        hard?

A. did you work    B. do you work     C. had you worked     D. have you worked

--- I’m sure Andrew will win the first prize in the final.

　 --- I think so. He ___________ for it for months.

　 A. is preparing B. was preparing　　

C. had been preparing D. has been preparing

The policeman’s attention was suddenly caught by a small box which ______ placed under the Minister’s car.

A. has been           B. was being    C. had been      D. would be

---Did you learn to drive 10 years ago?

---Yeah, I am sure he _________ for at least 10 years.

A. had driven             B. has been driven     C. has been driving       D. has driven