1. Doctors _____ an answer to AIDS yet.
A. have found                         B. found                C. haven't found           D. hasn't found
2. Do you mind _____ up?
A. wash                         B. washing           C. washed            D. to wash.
3. He _____ to give up smoking since last week.
A. was trying                           B. have tried         C. has tried                    D. tried.
4. He enjoys _____ in the rain.
A. walk                          B. walks               C. to walk            D. walking.
5. Would you like _____ to my party?
A. come                         B. to come            C. coming             D. came.
6. My sister likes _____ and _____.
          A. dance/sing                           B. to dance/sings  C.dancing/singing          D. dancing/to sing
7. This school _____ ten years ago.
A. be built                      B. is built             C. was built                   D. built
8. He _____ since the day we left school.
A. hasn't seen                                                       B. hasn't been being seen
C. wasn't seen                                                      D. hasn't been seen
9. We spent half a year _____ this hotel.
A. to build                     B. built                 C. building           D. with building
10. My friend is fond of _____ TV in the evening.
A. watching                             B. to watch                    C. watch               D. watched