1.

1-E

2-A

3-D

4-C

5-B

2.

6-Hurt

7-valuable

8-fever

9-sore

10-stomachache

11-toothache

12-argue

3.

13-shouldn't

14-should

15-should

16-shouldn't

17-should

4.

18-behind

19-apart

20-out

4-Наугад.