Ⅰ、D A C B
Ⅱ、F T F T T
Ⅲ、（单词至上而下）C A D B
Ⅳ、1、gym
2、dining hall
3、six months ago
4、last month
Ⅴ、1、is
2、weren't
3、was
4、were
5、couldn't
Ⅵ、A：1 - 5 A B B B C
B：例 :There was no library five years ago.There is a library now. There was no art room five years ago. There is a small art room now. There were many talk trees two years ago. Now there are some small trees. There were no TVs and computers in our schoo1、 There are many TVs and computers now.
Unit 4 Part B
Ⅰ、D A B C
Ⅱ、
| Then | weren't very strong；couldn't run fast or play basketball well |
| Now | can play basketball well |
Ⅲ、（词组至左而右）A C B
Ⅳ、1、couldn't
2、couldn't
3、was had
4、didn't
Ⅴ、1、It was small. Now it is big.
2、It was thin then.Now it is strong.
3、He was short then Now he is tall.
Ⅵ、T F T T
Unit 4 Part C
Ⅰ、1、go swimming
2、ride a bike
3、cook meals
4、play the piano
5、go ice-skating
6、play badminton
Ⅱ、C A B C B
Ⅲ、A：1 - 5 A B B C A
