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

→ if i had eaten lunch, I wouldn't have been hungry now

2. I only come if they invite me.

→ unless they invite, I won't come

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

→ if he had rivised all his lessons, he wouldn't have failed the exam

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

→ if you walk for 5 minutes, you will find the park

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

→ unless you leave me alone, I won't 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 doesn't snow, the children will go to school

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

→  had it not been for his dead, 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 will help you

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

→  were i take good care of it, the car wouldn't break down so often

$1.$ $→$ 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.

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