1. B

2. A

3. A

4. C

5. B

6. D

7. B

8. A

9. C

10. C

11. D

12. B

13. C

14. B

15. D

16. B

17. C

18. B

19. D

20. C

1. would be

2. would have waited

3. went

4. studied

5. is

6. made

7. had had

8. are

9. If I remembered his address I would send him an invitation

10. if john weren't working on two jobs right now he would have time to help you

A.I.1b are being built

2a should tell

3a should be banned

4c should

5b into

6d biodiversity

7b against

8a polluted

9c haven't seen

10c surface

11d had had

12b refused

13c closed

14b would get

15d didn't come

16b would be

II.17c danger

18b extinct

19d protect

20c hunted

B.I.1 would be

2 would have waited

3 went

4 studied

5 is

6 made

7 had had

8 are

II.9 If I remembered his address I would send him an invitation

10 if john weren't working on two jobs right now he would have time to help you