32. has become
33. with
34. to explore
35. However
36. prevent

Help

Ex1:
1. might have
2. had to 
3. didn't have to
4. could
5. shouldn't have
6. couldn't have
Ex2:
1. don't have to
2. must
3. Do you have to /don't have to / must
4. do not need to / must

help

6B 7C 8D 9C 10C 11D 12D 13B 14A 16B 17A 18A 19B 20C 21A 22B 23D 24B 25A 26C 27B 28A 29D 30B 31D

6B,7C,8D,9C,10C,11D,12D,13B,14A,16B,17A,18A,19B,20C,21A,22B,23D 24B,25A,26C,27B,28A,29D,30B,31D

b b c a d

1 B

2 B

3 D

4 A

5D 

1 A

2 B

3 D

4 C

5 D

6 C

7 D

8 A

9 B

10 B

11 B

12 D

13 C

14 B

b b c a d

b a b a b

A

C

B

1 C

2 A

3 D

4 A

5 B

II

1 B

2 A

3 C

4 A

5 B

1. C

2. A

3. D

4. A

5. B

1.Al Gore, who won the Nobel Prize, gave a long and boring speech.

2. Starbucks, which does business all over the world, wants to open new stores in China.

3. Social network sites, which are very popular, will definitely change business.

4. Scientists are working with stem cells, which will revolutionize medicine.

5. Last week, Jim Taylor interviewed Sally Thomson, who is my neighbour.

6. Mr Brown, who enjoys going to the theatre, has been invited to join our club.

7. Whiting House, which was built in 1856, is an important local monument.

8. Bono, who is a famous musician, signed autographs at Tower Records yesterday.

9. John F. Kennedy, who was president of the USA, was assassinated in 1963.

10. The Queen will open a new hospital, which is in Jarvis Street.