1. Why don’t study hard ?

=> If i were you, I would study hard

2. Keep silent or you’ll wake the baby.

=> If you don't keep silent, you will wake the baby up

3. I don’t know the answer, so I can’t tell you.

=> If I knew the answer, I would tell you

4. We got lost because we didn’t have the map.

=> If we had had the map, we wouldn't have got lost

5. My friend was so late, so he missed the train.

=> If my friend hadn't been so late, he wouldn't have missed the train

6. This car is too heavy for me to move.

=> If I were you, I wouldn't move this heavy car

7. Morning exercises make me feel healthy.

=> If you do morning exercise, you will feel healthy

8. The church bells keep me from sleeping.

=> If the church didn't bell, I could sleep

9. Without air, we would die.

=> If we live without the air, we would died

10. I advise him to stop smoking.

=> If I were him, I would stop smoking

11. Be calm, or you’ll make a wrong decision.

=> If you are not calm, you'll make a wrong decision

12. Without a visa, he couldn’t have come to that new country.

=> If he hadn't had a visa, he couldn't have came to that new country

13. Today isn’t Sunday, so the students don’t go swimming.

=> If today were Sunday, the students would go swimming

14. Because you don’t leave immediately, I call the policeman.

=> If you left immediately, I won't call a policeman

15. I don’t know her number, so I don’t ring her up.

=> If l knew her number, I could ring her up

16. Go right now or you will be late for the train.

=> If you don't go right now, you'll be late for the train

17. As she is often absent from class, she can’t keep pace with her classmates.

=> If she weren't absent from class ,she could keep pace with her classmate

18. I couldn’t write to Alice because I didn’t know her address.

=> If I know her adress, I could write to Alice

19. The heavy rain kept everybody from going outdoors.

=> If it hadn't been rained heavily, everybody would have gone out

20. I didn’t watch TV last night because I was busy.

=> If I hadn't been busy last night, I would watched TV

Chúc bạn học tốt, cho mình xin ctlhn nha :D

1. Why don’t study hard ?

⇒ If I were you, I would study hard.

2. Keep silent or you’ll wake the baby.

⇒ If you don't keep silent, you will wake the baby up.

3. I don’t know the answer, so I can’t tell you.

⇒ If I knew the answer, I would tell you.

4. We got lost because we didn’t have the map.

⇒ If we had had the map, we wouldn't have got lost.

5. My friend was so late, so he missed the train.

⇒ If my friend hadn't been so late, he wouldn't have missed the train.

6. This car is too heavy for me to move.

⇒ If I were you, I wouldn't move this heavy car.

7. Morning exercises make me feel healthy.

⇒ If you do morning exercise, you will feel healthy.

8. The church bells keep me from sleeping.

⇒ If the church didn't bell, I could sleep.

9. Without air, we would die.

⇒ If we live without the air, we would died.

10. I advise him to stop smoking.

⇒ If I were him, I would stop smoking.

11. Be calm, or you’ll make a wrong decision.

⇒ If you are not calm, you'll make a wrong decision.

12. Without a visa, he couldn’t have come to that new country.

⇒ If he hadn't had a visa, he couldn't have came to that new country.

13. Today isn’t Sunday, so the students don’t go swimming.

⇒ If today were Sunday, the students would go swimming.

14. Because you don’t leave immediately, I call the policeman.

⇒ If you left immediately, I won't call a policeman.

15. I don’t know her number, so I don’t ring her up.

⇒ If l knew her number, I could ring her up.

16. Go right now or you will be late for the train.

⇒ If you don't go right now, you'll be late for the train.

17. As she is often absent from class, she can’t keep pace with her classmates.

⇒ If she weren't absent from class ,she could keep pace with her classmate.

18. I couldn’t write to Alice because I didn’t know her address.

⇒ If I know her adress, I could write to Alice.

19. The heavy rain kept everybody from going outdoors.

⇒ If it hadn't been rained heavily, everybody would have gone out.

20. I didn’t watch TV last night because I was busy.

⇒ If I hadn't been busy last night, I would watched TV.