Modal Verbs

Noelia

What are modal verbs?

They are:• Can• Could• Must• Shall• Need• May• Might• Should• Will• Ought to

Modal verbs are sometimes referred to as

Modal Auxiliary verbs because they help other verbs

They are Auxiliary verbs that provide additional and specific

meaning to the main verb of the sentence

How do we use modals?

Example: Mary could play the piano

SSubject

VVerb

M

They do not accept conjugationThey do not need other auxiliary verbs

Form

He can ski. He cans ski or He can skis

Can he ski?Does he can ski?

They can’t ski. They don’t can ski

There is no “s” in singularThere is no “do / does” in the question

There is no “don’t / doesn’t” in the negative

Form

to can / caning to must /musting

She must studyWe should have gone the other wayHe could play football in his youthYou ought to go to the gym more often

Modal verbs do not have infinitives or –ing forms

Modal verbs are followed by an infinitive without to except for ought to

Form

Modal verbs do not have all the tenses

Modal verbs use other verbs to complete the tensesCan is completed with be able toMust is completed with have to

They can play the piano

They will be able to play the piano in the future

You must come early

You had to come early yesterday

What do they express?

They can have different meanings depending on the situations they are used

To understand it better we are going to divide them into 4 categories

1. Modal Verbs of obligation, no obligation, prohibition and advice.

2. Modal verbs of ability and permission.3. Modal verbs of speculation and deduction.4. Modals perfects: They are used to express a situation in the

past

CategoriesObligation, no

obligation, prohibition and

advice

Ability and permission

Speculation and deduction

Modal perfects

must/ mustn’t can / can’t

may may/might have

might / might not

should/shouldn’t have

have to/don’t have to

could / couldn’t must havecouldneedn’t

ought tocan’t havecan’tshould/

shouldn’t maycould havemustcan’t

Modals of obligation, no obligation, prohibition and advice

Modal Concept Examples

*1 MustHave to/has to Obligation You must decide now.

I have / she has to be fit to enter the race.

*2 Don’t have to/doesn’t have to

*3 Needn’t

No obligation(it’s not

necessary)

You don’t have / she doesn’t have to phone me tomorrow.

You needn’t meet me at the airport. I’ll get a taxi.

Ought toShould

Shouldn’tMust

Advice and recommendation

They ought to thank her for the present.You should stop smoking all the time.You shouldn’t cross the street without

looking first. It’s dangerous.You must try this recipe.

Mustn’tCan’t Prohibition

You mustn’t ride a motorbike without a helmet.

You can’t park here – look at the sign.

(*) Notes *1 In writing there is no real difference between these words. In speech

there is sometimes a small difference. Must is used when the speaker personally feels something is important and have to is used when the situation makes something necessary.

You must start working harder! (I say so)You have to turn left here. (it’s the law)

*2 Must and have to are very similar in their affirmative forms but they are completely different in their negative forms. Mustn’t describes sth which is prohibited. Don’t have to describes sth that is not necessary.

You mustn’t leave now. (it’s not allowed. It’s against the rules)

You don’t have to leave now. (it’s not necessary) *3 In informal spoken language we use don’t need to instead of needn’t.

You don’t need to go to the gym every day. You’re in good shape.

Modals of ability and permission

Modal Concept Examples

Can / can’t Ability in the present I can play the piano.My friend can’t speak Spanish

Could / couldn’t Ability in the past He could ski when he was 4.

I couldn’t ride a bike when I was a child

CanCouldMay

To ask permission and make polite

requests

Dad, can I go to the concert?Could I have some money, please?

May I come in, please?

CanCan’t

Permission in the present

You can borrow this CD if you like.Students can’t wear their own clothes to

school.

CouldCouldn’t

Permission in the past

I could stay out until midnight when I was 14.

We couldn’t wear jewellery at school.

Modals of speculation and deduction

Modal Concept Examples

*1 MayMightCould

Might notSpeculation

He’s wearing a ring, so he may be married.

I might go shopping later, I don’t know.It could rain today.

She might not be on the train.

Can’t Negative deduction That can’t be Sue. She’s in Brazil.

Must Affirmative deduction

You must be tired after your long journey.

*1 these words all express uncertainty or possibility. Could is not used with not in this context.The meaning for all three words is approximately 50% probability. But if we stress the modal verb strongly in speech the probability is reduced.

Modal Perfects

They are modals referred to actions that happened in the past

It must have been a difficult decisionThey should have invited her to their wedding

MODAL + HAVE + verb in past participle

Modal perfects

Modal Concept Examples

May have Past unreal possibility

We may have passed the test, but it was too difficult.

Might have Past unreal small possibility

She might have been swimming. Her hair is wet.

Should have Past unreal recommendation

You should have listened to the doctor.You shouldn’t have eaten too much

chocolate.

Must have Past unreal assumption

She looks very fit. She must have been to the gym a lot lately.

Can’t have Impossibility in the past

He can’t have stolen the money. He was with me all morning.

Could have Past unreal ability/possibility

She could have taken the flight.They could have won the match.

Practise1. My son ___ be home by now. Where can he be?

a. Have to b. Would c. Should d. Could

2. I think your thumb is broken. You ___ go to the emergency room.

a. Might b. could c. ought to d. can

3. If you are interested in losing weight, you ______ try this new diet.

a. Could b. mustn’t c. don’t have to d. had to

4. Johnnie’s fallen down the stairs! I ________ call an ambulance!

a. Will b. might c. may d. ought to

5. You _______ come too early. We won’t leave until 9 o’clock.

a. Has tob. must c. needn’t d. can’t

Practise6. Children ________ be accompanied by an adult at the zoo.

a. Ought to b. must c. would d. mustn’t

7. You _________ talk during tests. It’s forbidden!

a. don’t have to b. mustn’t c. couldn’t d. ought to

8. I can feel the heat. We _________ be near the fire.

a. Can b. wouldc. must d. have to

9. They ________ hear him because he was whispering.

a. Wouldn’t b. mustn’t c. shouldn’t d. couldn’t

10. You’ve never heard of Britney Spears! You ________ be serious!

a. Must b. had to c. can’t d. shouldn’t

Practise11. __________ you like to have dinner with me tonight?

a. Could b. may c. should d. would

12. You _________ let him hear about the party tomorrow. It’s a surprise!

a. mustn’t b. wouldn’t c. couldn’t d. can

13. __________ I speak to the Chief of Police, please?

a. Must b. May c. Would d. Need

14. He has arrived late. He _______ missed the bus

a. Must have b. Should have c. Could have d. must

More practise

Re-write the following sentences using modals so that they have the same meaning.

1. I suggest that you get a good lawyer!

You ___________________________________________

2. A university degree isn’t necessary for that job.

You ___________________________________________

3. Perhaps my father will pick you up.

My father _______________________________________

4. 4. Eating is forbidden in class!

You ___________________________________________

should get a lawyer

needn’t have a university degree for that job

don’t have to have a university…

may / might pick you up

mustn’t eat in class

More practise

Re-write the following sentences using modals so that thay have the same meaning.

5. Look at his dirty clothes! I’m sure he is a poor person.

He ____________________________________________

6. I don’t believe that the legend of Hercules is true because there’re many contradictions.

The legend of Hercules ____________________________

must be a poor person

can’t be true

Use your imagination

Think about these situations and create a sentence using modals.

1. We are going to Paris for a weekend. (Make suggestions about things to do)

2. We start school in September. (Talk about necessity)

3. Margaret is a very talented sportswoman. (Talk about ability)

4. You have just won the lottery! (Talk about possibility)

5. Peter has got a headache and a congested nose. (Give him some advice)

6. You want to borrow your uncle’s Mercedes Benz. (Ask for permission politely)

Possible answers

1. We could visit the Louvre / We should go up the Eiffel Tower

2. We have to buy a new notebook

3. She can speak 3 languages! / She is able to play the piano and the violin

4. I might stop working / I may buy a new car / I can travel to New York

5. You should see a doctor / You ought to drink hot tea

6. Can I borrow your car, please? or May I borrow your car, please?