5. She walked outside. Mary felt better. 9 (after) 6. The children cooked supper. Mother came home. (before)
7. I took a tablet of aspirin. Doctor arrived. (before).
8. Tom did his lessons. He went to play football. (after)​

Если переделать предложения, то

5. Mary felt better after walking outside

6. The children cooked supper before mother came home

7. I took a tablet of aspirin before Doctor arrived

8. Tom went to play football after he did his lessons