Exercise 7:
1. bad
2. suffer
3. sick
4. allergy
5. worse
6. tired
7. toothache
8. flu
9. vegetables
10. and

Exercise 8:
1. Do more exercise if you want to lose weight.
2. I have a lot of homework to do this evening, so I don't have time to watch the football match.
3. Eat more vegetables, and you will feel healthier.
4. Take up a new hobby, and you'll have some new friends.
5. Eat more fish, and you will be smarter.
6. He has toothache, but he still eats a lot of sweets and cakes.
7. Try to talk less if you have a sore throat.
8. Smoke less or give it up.
9. Sunbathe less, or you'll get sunburnt.
10. If you spend less time on computer games or television programmes, you will have more time for outdoor activities.