Ex1

1. B

2. C

3. B

4. A

5. B

6. C

7. A

8. B

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Ex2

1. atmosphere

2. shelter

3. extended

4. overcrowding 

5. packed

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Ex3

1. the best

2. faster

3. the least

4. better

5. prettier

6. good

7. happiest

8. the better

9. few

10. the farthest

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Ex4

1. easier

2. more expensive 

3. the most unusual

4. more interesting 

5. the most difficult 

6. worse

7. the hardest 

8. thinner

Exercise 1

1.B

2.C

3.B

4.A

5.B

6.A

7.C

8.B

Exercise 2: Complete the sentences using the given words.
              
1.Many people prefer to live in the countryside rather than in big cities because of its peaceful .atmosphere ( không khí ) 
2.Refugees and homeless people in the city need to be donated food to eat and a.shelter ( nơi trú ẩn ) to sleep.
3.The roads are extended ( mở rộng )as one of the solutions to deal with traffic jams.
4overcrowding ( đông ).in the neighborhood is one of the causes of social evils.
5.We decided to move to another restaurant because the other restaurant was.packed ( chật cứng )

Exercise 3: 

 1.the best

 2.faster

 3. the least

 4.better

 5.prettiest

 6.good

 7.happiest

 8. the best

 9.few

 10.the farthest

Exercise 4:

1.easier 

2.more expensive

3.the most unusual

4.more interesting

5.most difficult

6.worse

7.hardest

8.thinner