1. If you want to be an astronomer, you need to study Physics.
2. I'd come to the party if I didn't have an exam tomorrow.
3. Kate won't go out unless the weather improves.
4. If you want to come with us, I'll give you a lift.
5. If students fail the exam, they can take it again.
6. If you could go anywhere in the world, where would you go?