12. _____ your letter, I would have started off two days ago.

　 A. If I received 　　　　　　　　　　　　　　 B. Should I receive　　　　

C. If I could have received　　　　　　　 D. Had I received

11. If it _____ for the snow, we _____ the mountain yesterday.

　 A. were not; could have climbed　　　　　　 B. were not; could climb

　 C. had not been; could have climbed　　　　 D. had not been; could climb

10. --Where have you been?

　 --I got caught in traffic; _____ I could have been here soon.

　 A. otherwise 　　 B. however　　　　　　 C. though 　　 D. anyway

9. Without sunlight or water or air, there _____ no life on the earth.

　 A. will have　　　　　　　 B. would be　　 　 C. should be　　　 D. must be

8. John was very busy last week, otherwise, he _____ to attend the meeting.

　 A. would have come 　　B. would come 　　　　　　　

C. should come　 　　　 D. came

7. Without your help, I _____ in my English study.

　 A. would not have succeeded 　　　　　 B. hadn’t succeeded

　 C. will not succeed　　　　　　　　　　　　　 D. won’t have succeeded

6. If he came here at this moment, I _____ him.

　 A. would criticize　　　 　　　 　B. will criticize　　　　　　

C. shall criticize　　　　 　　　 D. were to criticize

5. If it _____ yesterday, we could play football on the sports ground now.

　 A. didn’t snow　 　　　 B. hasn’t snowed　　　

C. hadn’t snowed 　　 　　D. weren’t snowing.

4. Everybody would be very happy if the hot summer _____ tomorrow.

　 A. should finish　　　　　　　　　　　　　　　 B. would finish 　　

C. were to be finished　　　　　　　　　　　　　　 D. finishes

3. If I _____ you, I would ask him to stay.

　 A. was　　　　 B. would be　　　　 C. were　　　　　 D. am