1. He will pay me tonight; I will have enough money to buy a car.

> If .....he pays me tonight, I will have enough money to buy a car.........................

2. I will get a work permit. I will stay for another month.

> If ........I get a work permit. I will stay for another month...................

3. I only come if they invite me.

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

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

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

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

> Had ..he not died so young, he would be a famous musician by now..........................

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

> Were I to take good care of the car, it wouldn't break down so often ................................

7. She got married at such an early age; otherwise, she would be at university now.

> Had .she not got married at such an early age, she would be at university now. ...............................