1, 1) He can’t go out because he has to study for his exam. => If……. 2) She is lazy so she can’t pass the exam. If……. 3) He will pay me tonight; I will have enough money to buy a car. => If……. 4) He smokes too much; that’s why he can’t get rid of his cough. => If……. 5) She is very shy, so she doesn’t enjoy the party. => If……. 6) I will get a work permit. I will stay for another month. => If……. 7) He doesn’t take any exercises. He is so unhealthy => If……. 8) We can’t get the ticket because I don’t have the right change. => If……. 9) Study hard or you won’t pass the exam. => If……. 10) Don’t be impatient or you will make mistakes. If…….

1) He can’t go out because he has to study for his exam.
=> If he had to study for his exam, he could go out.
2) She is lazy so she can’t pass the exam.
=>If she were lazy, she could pass the exam.
3) He will pay me tonight; I will have enough money to buy a car.
=> If he pays me tonight, I will have enough money to buy a car.
4) He smokes too much; that’s why he can’t get rid of his cough.
=> If he didn’t smoke too much, he could get rid of his cough.
5) She is very shy, so she doesn’t enjoy the party.
=> If she weren’t very shy, she would enjoy the party.
6) I will get a work permit. I will stay for another month.
=> If I don’t get a work permit, I won’t stay for another month.
7) He doesn’t take any exercises. He is so unhealthy
=> If he took any exaecises, he were so healthy.
8) We can’t get the ticket because I don’t have the right change.
=> If we could get the ticket, I would have the right change.
9) Study hard or you won’t pass the exam.
=> If you study hard, you will pass the exam.
10) Don’t be impatient or you will make mistakes.
=> If you are impatient, you will make mistakes.

- Nếu câu đề là hiện tại - hiện tại / tương lai thì dùng loại 2 + phản nghĩa .
- Nếu câu đề là : tương lai - tương lai thì dùng loại 1 (không phản nghĩa )
If I go to VT, I will buy you a present.
- Nếu câu đề là : Don’t V…….or + mệnh đề thì viết lại là :
If you V ( viết lại hết ,bỏ or )
- Nếu câu đề là: V …….or + mệnh đề thì viết lại là :
If you don’t V ( viết lại hết ,bỏ or )