Bài 1:

1 beautiful→more beautiful→the most beautiful

2 hot→hotter→the hottest

3 crazy→crazier→the craziest

4 slowly→slowlier→the slowliest

5 few→fewer→the fewest

6 little→littler→the littlest

7 bad→worse→the worst

8 good→better→the best

9 attractive→more attractive→the most attractive

10 big→bigger→the biggest

Bài 2:

1C

2B

3C

4A

5C

6D

7A

8A

9A

10D

11C

12C

13D

14A

15A

16C

17A

18A

19A

20B

Bài 3:

1 the cleverest

2 longer

3 the best

4 cleaner

5 more expensive

6 quicker

7 more dangerous

8 sweeter

9 the most exciting

10 the fastest

11 the most popular

12 the closest

13 beautiful

14 hotter

15 worse

16 better

17 bigger / bigger

18 more difficult / the most difficult

19 largest

Bài 4:

1 thinner than

2 more intelligent than

3 the coldest

4 more expensive

5 the most beautiful

6 better

7 the longest

8 the best

9 the most beautiful

10 better than

11 the most comfortable

12 more carefully than

13 more expensive

14 more beautiful than

15 the largest

16 the fastest

17 fewer

18 the biggest

19 noisier than

20 the cleverest

21 more fluent than

22 the most polite

23 happier

24 the most graceful

25 clearer

26 higher

27 more careful

28 faster

29 worst

30 harder