Ответ:

1) prettier, the prettiest

2) taller than, the tallest

3) interesting, more interesting than

4) better than, the best

5) happy, the happiest

6) sad, sadder than

7) more unusual than, the most unusual

8) bad, the worst

9) short, shorter than

10) more amazing than, the most amazing

11) red, the reddest

12) green, greener than

13) sleepier than, the sleepiest

14) more wonderful, the most wonderful

15) terrible, more terrible

16) large, larger

17) hot, the hottest

18) more expensive, the most expensive

19) old, older

20) more fascinating, the most fascinating ( потом добавите than  там где я пропустила, лень писать)

Объяснение: