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Modal Auxiliariespresent and future:

• Ability • Can and be able to• Be able to is used in situations where can does

not have the necessary grammatical form. I'd like to be able to swim. Not being able to swim

is annoying. Can is also used with ‘be’ to make criticisms.You can be really annoying, you know! Can is used with ‘be’ for capability.Winter here can be really cold.• Fenerbahce stadium can take 30 thousand people.

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Certainty and uncertainty

• Must and can't

• These are used to make deductions, when we are more or less certain about something, especially with the verb to be.

You must be tired after your journey.

(I suppose you are)

That can't be Sue. She's in Brazil. (I'm sure it's impossible)

• The plane must arrive soon.

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May, might and could• These all express uncertainty or possibility.

They are usually stressed in speech. • Might is less likely than may. • May and might express possibility or

uncertainty The committee may find a solution to the

problem.∀ • Could is not used with not in this context. It may not rain. I might go out, I don't know. I could get wet!

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• May is used to express although clauses ( but, however, although, though, etc…)

He may be the boss, but that is no excuse for shouting like that.

• May / might as well describe the only thing to do, something which the speaker is not enthusiastic about.

Nobody else is going to turn up now for the lesson, so you may as well go home.

• With an idiomatic expression with ‘try’, using may for the present reference, and might for the past reference.

• Try as I might, I couldn’t pass my driving test. (Although I tried hard, I couldn’t pass my driving test.)

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Could is used:• Possibility or uncertainty

This could be the house. • With comparative adjectives to express

possibility or impossibility.

The situation could be worse. It could be better.• To make suggestions.

We could eat at home tonight.• To express unwillingness.

I couldn’t possibly leave Tom here on his own.

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shall• Shall can be used with all persons to emphasise

something which the speaker feels is certain to happen or wants to happen.

I shall definitely give up smoking this year.

We shall win. ( it is stressed in the sentence)• Shall is used in formal rules and regulations.

No player shall knowingly pick up or move the ball of another player.

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Will • Will is used to express assumption.-- The phone is ringing. --That will be for me.• Will and Won’t is used emphatically to tell

someone of the speaker’s intention, or to forbid an action, in response to a will expression.

• -- I will take the money anyway ! -- You won’t ! -- I will !• And I won’t can mean ‘I refuse.’ I will can

mean ‘I insist.’ -- I won’t do it! -- Yes, you will!

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Would • Would can refer to an annoying event,

typical of a person.

James would get lost, wouldn’t he! It is typical!

• Would also expresses certainty, where the sentence is a hidden conditional sentence.

Nobody would agree with that idea. ( if we asked them)

Life wouldn’t be worth living without you. ( if you weren’t there.)

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• Would can be used with ‘be’ followed by an adjective doubtful, unlikely to emphasise an uncertain action.

• Also after doubt in the same way.

It is unlikely that Jane would do something like that.

I doubt whether Heidi would know the answer.

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Need • It is used as a normal verb.

Do you need to use the photocopier?

• used as a modal verb, but in questions and negatives.

Need you make so much noise?

You don’t need to come to school.

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. be bound to

• This refers to the future, whereas must refers to the present.

You 're bound to see Paula If you go there. {I'm sure you will)

You must see Paula if you go there. (An obligation)

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Obligation

• Must and have to• Have to describes obligations made by someone

else, while must is used to describe a personal obligation. There may be no difference.

• You must start working harder! (I say so) • You have to turn left here. (It's the law) • Sorry, I must leave / have to leave now. (No

difference)

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• Mustn’t and don't have to• Mustn't describes something which is not

allowed or an obligation not to do something.

You mustn't leave any bags here. (It's against the rules)

You mustn’t leave the class before the end of the test.

• Don't have to describes something which is not necessary or absence of obligation.

You don't have to apply yet. (It's not necessary)

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Should and ought to • These have the same meaning. They

describe 'what is a good idea' and can be used to give advice, or polite instructions.

I think you should see a doctor You ought not to continue.

You should send in your application by July 18th.

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Should is used • As expectation• Should can also describe actions we expect to

happen.Brenda should be home by now. (She is expected

to be)• As recommendation. I think you should talk it over with your parents.• As a strong obligation politely, in writing.Guests should vacate their rooms by midday.• As criticismYou shouldn’t eat so much late at night.

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• Uncertainty

• Should I leave these papers on your desk?

• With be and adjectives describing change like odd, strange, funny and with the expression ‘ what a coincidence!’

• It is strange that you should be staying in the same hotel.

• To emphasise unlikelihood with ‘in case’

• I am taking an umbrella in case it should rain.

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Had better • This refers to present or future time, and

gives advice about how to stop something going wrong.

• I think you'd better leave now. (Before it is too late)

• You 'd better not drive. (It might be dangerous)

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Is / Are to

• This is used in formal instructions. Not is stressed.

No one is to leave the room.

You are not to leave the room.

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• Be careful with these;

• Most modal auxiliaries have more than one meaning. You may have to think carefully about the context to understand the meaning.

• The negative forms mustn't and don't have to have different meanings.

• You mustn't go. (It is against the rules)

• You don't have to go. (It isn't necessary)

• Should is a weaker obligation than must and have to.

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exercises

• Choose the most suitable word or phrase.

• There's someone at the door. It ………….. postman. He always comes at this time.

A) can be B) must be

C) might be D) should

• must be

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2. Don't worry, you …………… pay now.

A) don't have to

B) mustn't

C) can’t

D) mightn’t

• Don’t have to

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• I think you …………… take a pullover with you.It may get colder later.

• A) had better B) would better C) would rather D) would like

• Had better

• Jones …………… president if Smith has to resign since he is the only one who can handle the pressures of the public.

• A) could be B) must be

• C) had to be D) were to

• Must be

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• Sorry, I can't stay any longer. I …………… .

• A) have to go B) might go C) can go D) may go

• have to go

• It was 5 o'clock an hour ago. Your watch ………….right.

• A) can't be B) mustn't be

• C) needn’t D) doesn’t have to be

• can’t be

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1. It's a school rule, all the pupils ………a uniform.

A) have to wear B) must wear C) can wear D) are allowed to wear

3. Have to wear

4. I suppose that our team ………….. but I'm not sure.

A) must win B) should win C) have to win D) is allowed to win

• Should win

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• Let us tell Diana. She .............. know.

• A) could not B) might not

• D) must not D) need not

Might not

In my opinion, the government .......... something about this.

• A) might do B) should do

• C) Could do D) may do

• Should do

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• Don't stand up in the boat! You ……....... fall in the river!

A) might B) must C) should D) are able to• might 12. Sue says she's stuck in the traffic and

she.................. be late. A) might B) must C) ought to D) should• might

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• 13. You really.................. start spending more time on your work.

• A) might B) must • C) can D) could• must• 14. Tell Peter he.................. stay the night

here if he wants to.• A) might B) must • C) should D) ought to• might

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• 15. That's a really stupid idea! You .................. be serious, surely!

• A) might B) must • C) mustn’t D) can’t• can’t

• 16. You ......... ....... realise it, but this is very important to me.

• A) mightn’t B) mustn’t • C) can’t D) shouldn’t• mightn’t

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• 17. Don't be silly. You .................. expect me to believe you!

• A) mightn’t B) can’t • C) mustn’t D) shouldn’t• can’t

• 18. We're not sure but we.................. go to Prague for Christmas this year.

• A) might B) must C) should D) ought to

• might

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• 19. Me learn to fly! You .................. be kidding!

• A) might B) can’t

• C) must D) mustn’t

• must

• 20. Bill cooked the lunch, so you .................. expect anything special!'

A) mightn’t B) might

C) shouldn’t D) can

• shouldn’t

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• 21. I don’t think you …………… tell anyone yet.

• A) could B) should • C) might D) can• should• 22. I …………. possibly leave without paying.• A) couldn’t B) shouldn’t • C) mustn’t D) don’t have to• Could not

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