Đáp án+Giải thích các bước giải:

Bài 1: 

\begin{array}{|c|c|c|}\hline \text{Tính từ}&\text{So sánh hơn }\\\hline \text{cheap}&\text{cheaper}\\\hline \text{cold}&\text{colder}\\\hline \text{thin}&\text{thinner}\\\hline \text{good}&\text{better}\\\hline\text{fast}&\text{faster}\\\hline \text{big}&\text{bigger}\\\hline \text{high}&\text{higher}\\\hline \text{long}&\text{longer}\\\hline \text{pretty}&\text{prettier}\\\hline \text{heavy}&\text{heavier}\\\hline \text{narrow}&\text{narrower}\\\hline \text{old}&\text{older}\\\hline \text{near}&\text{nearer}\\\hline \text{bad}&\text{worse}\\\hline \text{fat}&\text{fatter}\\\hline \text{ugly}&\text{uglier}\\\hline \text{clever}&\text{cleverer}\\\hline \text{close}&\text{closer}\\\hline \text{safe}&\text{safer}\\\hline \text{far}&\text{farther}\\\hline \text{large}&\text{larger}\\\hline \text{noisy}&\text{nosier}\\\hline \end{array}

Bài 2:

Công thức so sánh của tính từ ngắn:   `S_1 +V_1+` adj/adv `+` _er` + than +S_2`

Công thức so sánh của tính từ dài: `S_1 +V_1+`more` +` adj/adv `+than +S_2`

1. more beautiful 

2. more expensive 

3. more dangerous

4. more comfortable

5. more convenient

6. more important

7. more execiting

8. more popular

9. more beautiful

10. more difficult

11. more inconvenient

12. more modern

13. more historic

14. more terrible

15. more polluted

16. more crowed

17. more boring

Bài 3:

1. Nam's new school is bigger than old his one.

2. Huy is taller than his brother.

3. This chair is more comfortable than that one.

4. Living in the countryside is more peaceful than living in the city.

5. He is more intelligent than his friend 

6. The country is quieter than the city.

7. She incredibly dislikes her family's art gallery

8. The statue is located between a temple and a railway station.

So sánh hơn của ADJ/ADV ngắn 
S + be/V + ADJ/ADV + ER + than ……
So sánh hơn của ADJ/ADV dài 
S + be/V + more + ADJ/ADV + than ……
ADJ ngắn là từ có 1 hoặc 2 âm tiết tận cùng là - er, -ow, - y 
- Tận cùng là y → đổi -y thành - i và thêm ER 
- Tận cùng là e → thêm R  
- Phụ + nguyên + phụ âm → ta gấp đôi phụ âm cuối → và thêm ER 

ADJ + ly --> ADV dài

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Bài 1: 

1. cheaper 

2. colder

3. thinner

4. better

5. faster

6. bigger

7. higher

8. longer

9. prettier

10. heavier

11. narrower

12. older 

13. nearer

14. worse

15. fatter

16. uglier

17. cleverer

18. closer

19. safer

20. farther / further

21. larger

22. noisier

Bài 2: 

1. more beautiful

2 more expensive

3. more dangerous 

4. more comfortable

5. more convenient

6. more important

7. more exciting

8. more popular

9. more beautiful

10. more difficult

11. more inconvenient

12. more modern

13. more historic

14. more terrible

15. more polluted

16. more crowded

17. more boring

Bài 3:

1. Nam's new school is bigger than his old one.

2. Huy is taller than his brother.

3. This chair is more comfortable than that one.

4. Living in the countryside is more peaceful than living in the city.

5. He is more intelligent than his friend.

6. The country is quieter than the city.

7. Incredibly, she dislikes her family's art gallery.

8. The statue is located between a temple and a railway station

`color{orange}{~LeAiFuRuiHuiBao~}`