Revision questions: modals
- What is the past equivalent of I must give up smoking: I had to give up smoking or I must have given up smoking?
- What time does It was going to rain refer to?
- Can we use a perfect infinitive after a modal verb that refers to past time?
- What does He might have died mean?
- What is the difference between I didn't need to worry, I needn't have worried and I shouldn't have worried?
- What does can't in You can't be serious express: ability, deduction or prohibition?
- Which modals can be used to express suggestions, offers and requests?
- What is the difference in usage between can and may for permission?
- What is the difference in usage between used to and would for past habits?
- Can will be used to refer to past time?
