IF or UNLESS

Rewrite these sentences using IF or UNLESS.
1. If you don't start now, you will not reach there in time.
2. I will take the job unless the pay is too low.
3. I will be surprised if he doesn’t have an accident soon.
4. If she doesn’t stop smoking, she will fall seriously ill.
5. The situation won't get better unless we do something immdiately.
6. You will never understand English grammar unless you study this language.
7. If he doesn't hurry up, he will be late.
8. Beer is great if unless you drink too much of it.
9. Unless the teacher needs more space, this small classroom will be OK.
10. If it doesn't stop raining, we will not have a picnic.