Unreal past

In each of the following sentences, choose the correct tense

1. He
   [could have passed|could pass] his exams if he had studied harder.
2. If her car
   [hadn't broken down|didn't break down], she wouldn't have walked to work.
3. Suppose you
   [had seen|saw] someone stealing your neighbour's car, what would you do?
4. If only Mark
   [didn't lie|hadn't lied] to me.
5. It's about time they
   [moved|had moved] to a bigger house.
6. I wish we
   [have been|were] on a cruise ship.
7. I'd rather you
   [had done|did] the shopping today.
8. I wish I
   [had|have had] enough money to buy a new car.
9. I'd rather you
   [hadn't said|didn't say] anything to Richard.
10. Suppose you
    [were caught|had been caught] cheating, what would have happened?