1. He was tired. He made a mistake.
=> If he hadn't been tired, he wouldn't have made a mistake
2. It stops raining. We will go out.
=> If it didn't stop raining, we wouldn't go out
3. Your English isn't good. You won't be able to do this exercise.
=> If your English were good, you would be able to do this exercise
4. You give back my bicycle, or I will call the police.
=> If you don't give back my bicycle, I will call the police
5. He is very slow, so we won't give him an important task.
=> If he weren't very slow, we would give him an important task 
6. He can't go out because he has to study for his exam
=> If he didn't have to study for his exam, he could go out

1 . IF HE HADN’T BEEN TIRED, HE WOULDN’T HAVE MADE A MISTAKE.

2. If it doesn't stop raining,we won't go out

3 If your English weren't good, you wouldn't be able to do exercise.

4 If you don't give back my bicycle, I will call the police.

5 If he weren't very slow ,we would give him an important task

6 If he didn't study for his exam,he could go out