1: of
2: enough
3: runny
4: puts
5: tired
6: up
7: eating
8: less
9: temperature
10: stay
11: difficulty
12: joins
13: You should do more exercise
14: you should read more
15: You should watch less
16: you should drink more
17: I eat less junk food so I am putting on weight
18: Stay at home or I will be sick
19: I have a headache but I don't want to take some medicine
20: He likes reading books and playing football