`1`. If he didn't have to study for his exam, he could go out.
`2`. If she weren't lazy, he could pass the exam.
`3`. If he didn't smoke too much, he couldn't get rid of his cough.
`4`. If she had a college degree, she could be employed.
`5`. If she hadn't walked to the meeting, she wouldn't have been late.
`6`. If the weather hadn't been terrible, we wouldn't have put off our trip.
`7`. If you don't leave me alone, I will call the police.
`8`. Were you to take good care of the car, it wouldn't break down so often.
`9`. If you tell lies to your boss, you will be fired at once.
`10`. Had he revised all his lessons, he wouldn't have failed the exam.
`11`. If the driver in front hadn't stopped so suddenly, the accident wouldn't have happened.
+) Giải thích:
Câu điều kiện loại 1: If + S + V(s,es) + O, S + will/can/may + V + O
Câu điều kiện loại 2: If + S + Ved + O, S + would/could/might + V + O.
Đảo ngữ câu điều kiện loại 2: Were + S + to V + O, S + would/could/might + V + O.
Câu điều kiện loại 3: If + S + had + Ved/PII + O, S + would/could/might + have + Ved/PII + O.
Đảo ngữ câu điều kiện loại 3: Had + S + Ved/PII + O, S + would/could/might + have + Ved/PII + O.