1.⇒ If I had eaten lunch, I wouldn't have felt hungry now.

2.Unless they invite me, I won't come.

3.If he had revised all his lessons, he wouldn’t have failed the exam.

4.If you walk to the park, it will take you 5 minutes.

5.Unless you leave me alone,I'll call the police.

6.Should you arrive at the office earlier than I do, please turn on the air- conditioner.

7. If it snows, the children won't go to school.

8.Had he not died so young, he would have been a famous musician by now.

9.Unless you tell me the whole truth, I won't help you.

10. Were I to you, I would take good care of it.

1. I didn’t eat lunch, I feel hungry now.

–> If I had eaten lunch, I wouldn’t feel hungry now.

2. I only come if they invite me.

–> Unless they invite me, I won’t come.

3. He didn’t revise all his lessons, he failed the exam.

–> If he had revised all his lessons, he wouldn’t have failed the exam.

4. The park is over there, only 5 minutes’ walk.

–> If you walk to the park, it will take you 5 minutes.

5. Leave me alone or I’ll call the police.

–> Unless you leave me alone, I’ll call the police.

6. If you arrive at the office earlier than I do, please turn on the air-conditioner.

–> Should you arrive at the office earlier than I do, please turn on the air-conditioner.

7. The children don’t go to school in the snowy weather.

–> If it snows, the children won't go to school.

8. He died so young; otherwise, he would be a famous musician by now.

–> Had he not died so young, he would have been a famous musician by now.

9. You must tell me the whole truth or I won’t help you.

–> Unless you tell me the whole truth, I won’t help you.

10. The car breaks down so often because you don’t take good care of it.

–> Were I you, I would take good care of it.