Ex7:
1. If Oanh had know how to solve the maths problem, she wouldn't have got low marks.
2. If you had said sorry, she wouldn't have got angry.
3. If they had passed the exam, their family wouldn't have been sad.
4. If it hadn't rained a lot yesterday evening, we would have gone swimming.
5. If the weather had been fine enough, I would have gone camping.
6. If the computer hadn't broken down, she wouldn't have had to stop her work.
7. If we had said anything to Thanh, she wouldn't have been angry.
8. If our teacher had come, we wouldn't have canceled the party.
9. If Quang hadn't been interested in the film, he would have studied his lesson.
10. If I hadn't had a bad headache yesterday, I would have gone to school.
