1. He can't go out bacause he has to study for his exam.

=> If .........he didn't have to study for his exam,he could go out.........

2. She is lazy so she can't pass the exam.

=> If ................. she weren't lazy, she could pass the exam.........

3. H will pay me tonight; I will have enough money to buy a car.

=> If ....H doesn't pay me tonight, I won't 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 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....