Must & Have to

'must' is used to show that we are sure something is true. It is a logical deduction based upon some clear evidence or reason.

· It must be nice to live in Florida where the weather is always good.

· There's no heating on. You must be cold.

· You must be worried about her. She is very late coming home.

· I can't remember what I put it. I must be getting old.

'must' is also used to express a strong obligation. We use 'must' when it is some personal circumstance that makes the obligation necessary (and the speaker almost certainly agrees with the obligation.)

· They must do something about this road. It is very dangerous.

· I must go to bed earlier in future.

· You must come and see us when you next come to England.

· I must say, I don't think you were very polite to him.

We also use 'have to' to express a strong obligation. When we use 'have to' this usually means that some external circumstance makes the obligation necessary.

· We have to put in our offer today or lose out on the contract.

· I have to arrive very early. My boss is very strict.

· You have to get good grades in your exams or the university will not accept you.

· I have to send a report to my manager every week.

In British English, 'have got to' is used in the same way as 'have to'.

· We've got to finish now. Our time is up.

· I've got to take this dress back to the shop and get it changed.

'will have to' is also used to talk about strong obligations. Like 'must' this usually means that that some personal circumstance makes the obligation necessary. (Remember that 'will' is often used to show 'willingness'.)

· We'll have to do something about it.

· You'll have to speak to her.

· We'll have to have lunch and catch up on everything.

· I'll have to get back to you later.

As you can see, the differences between the affirmative forms are sometimes very small and very subtle. However, there is a huge difference in the negative forms.

'mustn't' is used to express strong obligations NOT to do something.

· You mustn't leave your door unlocked. Something will get stolen.

· You mustn't talk about it. It's confidential.

· I mustn't drink. I'm driving tonight.

· You mustn't phone me at work. We aren't allowed personal calls.

'don't have to' (or 'haven't got to' in British English) is used to state that there is NO obligation or necessity, it is a question of choice.

· You don't have to book. You can buy a ticket when we get there.

· I don't have to listen to this. I'm leaving.

· You don't have to do it if you don't want to.

· She doesn't have to sign anything at this stage.

· I haven't got to go just yet. I've got another hour.

Дата добавления: 2015-11-14