`3.`If the rain hadn't been heavy, we wouldn't have come to the class late.

`4.`If she hadn't felt so tired, she could have gone to the cinema with us.

`5.`If my father hadn't gone to work yesterday, he would have known what happened to me.

`6.`If the teacher's question hadn't been so difficult, I could have answered.

`7.`If he hadn't started earlier, he would have missed the first bus.

`⇒`Cấu trúc :

- Câu điều kiện loại 3 : If + S + had Vpp, S + would/could/should (not) + have + Vpp

`⇒`Câu điều kiện Loại 3 là câu mệnh đề chỉ điều kiện không có thật ở quá khứ, đưa ra môt giả định/giả thiết trái ngược hoàn toàn so với thực tế xảy ra 

- Khi chuyển từ Unless về If, ta giữ nguyên 1 vế và trái vế còn lại

Đáp án:

3. Because of the heavy rain, we came to the class late.

=> Unless the rain had been heavy, we wouldn't have come to the class late.

4. She felt so tired and she couldn’t go to the cinema with us.

=>Unless she had felt so tired, she could have gone to the cinema with us.

5. My father went to work yesterday so he didn’t know what happened to me. 

=>Unless my father had gone to work yesterday, he would have known what happened to me.

6. The teacher’s question was so difficult that I couldn’t answer. 

=>Unless the teacher's question had been so difficult, I could have answered.

7. He missed the first bus because he didn’t start earlier. 

=>Unless he had started earlier, he would have missed the first bus.

Giải thích:

Unless=If not

ĐK loại 1: Unless(If not)+ S + V (simple present), S + will/can/shall + V

ĐK loại 2: Unless (If not)+ S +Ved / V2 (simple past), S+ would + V

ĐK loại 3: Unless (If not)+ S + had + Ved/V3 , S + would + have + Ved/V3