mo dals theory blog

7/30/2019 Mo Dals Theory Blog

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MODAL VERBS

GENERAL FEATURES

These are the English modals verbs:

- Can - Could- MayMight- MustShallShould- Will - Would - 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.

1.- Modals don't have all the verb forms or tenses (infinitive, past simple ,past

participle, -ing form): only 1 form. The verb form is the same for all the persons.

Modal verbs use other verbs to complete the tenses: For example, Can is completed

with be able to; and Must 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.

2.- Their meaning can change when they are used in the affirmative, the negative or the

interrogative forms.

3.- They don't need auxiliary verbs to form the interrogative and negative forms:

E.g. You can't choose the PM. He shouldn't behave in that way. Should I go to the

doctor?

4.- They are ALWAYS followed by infinitive without to (except OUGHT TO)

5.- To form the negative, we add NOT to the modal verb:

E.g. A jury might not believe him

6.- Semi-modals: some modals share features of the common verbs and others of the

modals verbs, and they are called semi-modals: these are HAVE TO and NEED

Have to: it needs auxiliaries for the negative and the interrogative; it takes sfor the present 3

rdperson singular.

Need : It is used as a modal and as a normal verb. Modal Verb: It doesnt take an auxiliary verb. He needn't

come.

Ordinary verb: He doesn't need to be there. informal language7.- Modal Perfect tenses (modal + have+ participle) are used to refer to actions in the

past.

e.g. He looks exhausted. He must have been working really hard.

EXPRESSING OBLIGATION

MUST:Personal obligation coming from the speaker: It refers to the present/future

- I must study harder to pass this year.Remember: The negative of must means prohibition (You mustnt park here)


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HAVE TO: This is not a modal verb, and so it needs an auxiliary to form the negative

and the interrogative. It can be formed in any tense, and it replaces the modal Must for

those tenses this one lacks. In the present, it expresses an obligation made by other

person, an order, a regulation, a law:

- I have to wear a helmet when I drive my motorbike.

- Does she have to study at school up to 16?

HAD TO: In the past, it relates both to the past ofmust and to the past of have to

-I had to take my sister to her tennis lesson

-Did you have to wear a school uniform?

EXPRESSING LACK/ABSENCE OF OBLIGATION OR NECESSITY

DON'T HAVE TO: to express that something is not compulsory or obligatory. It is used

for present and past situations.

- You don't have to attend the conference. - She didnt have to answer all questions.

- She doesnt have to leave early tomorrow

NEEDN'T: We use it to talk about something which is not obligatory in the present. The

modal need (without to) is only used in the negative and the interrogative. In the

affirmative, it expresses necessity and its used as a common verb.

- You neednt visit my uncle but you need to visit the doctor.

-Youll need to take warm clothes.

-Did you need to use the dictionary?

Similarly, well use need + to+ infinitive for the future and the past, as the last 2

examples show.

NEEDNT + have + participle: a past activity which took place, but which was

unnecessary:

- You neednt have brought a present for the birthday party! (but you brought it!)

-I neednt have taken my umbrella.

On the other hand, didnt need + infinitive refers to an unnecessary action:

- I didnt need to wake up early (maybe I did or I didnt, the point is that it was not

necessary)

EXPRESSING PROHIBITION

CAN'T:

MUSTN'T: stronger prohibition

You can't eat sweets before dinner You mustn't smoke at school.

EXPRESSING ADVICE/RECOMMENDATION in the present:

SHOULD/ SHOULDN'T: it refers to the present

- He should get up earlier.- He shouldn't wear so tight clothes because they make him look fatter.

OUGHT TO: it refers to the present.

- She ought to go to the gym


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MUST:It expresses astrong recommendation in the present.

- I have just read this novel. You must read it. It is wonderful.HAD BETTER (NOT): to give strong advice ad warnings in the present

- Youd better go or you wont be on time- Youd better not do that or Ill get angry

HAD BETTER NOT is also used to threaten someone: Shed better not tell anything

or shell be reported to the police.

EXPRESSING CRITICISM OR ADVICE in the past

SHOULD/ SHOULDN'T + have + participle:This describes a criticism or regret about

a past action. It also refers to a not followed advice.

- You should have told them the truth.

- We shouldnt have left before the concert ended.

OUGHT TO + have+ participle: (as above)

-We ought to have waited for her.

EXPRESSING ABILITY

WILL (NOT) BE ABLE TO: It refers to ability in the future.

- I wont be able to get there until 3.00.

BE ABLE TO is used in the future, but also to express ability in the present and in the

past

-She was able to play the piano when she was seven

-Im not able to finish this exercise.

CAN / CANT:To express ability in the present.

-You can/cant swim well.

COULD / COULDNT: ability in the past

- She could dance when she was younger.

EXPRESSING PERMISSION

CAN / CANT in the present: You can/cant go to the party. (Here, it means that you

dont have permission to go)

COULD / COULDNTin the past: I could/couldnt drink Coke when I was five.

Be allowed to + infinitive: permission in any tense

-You arent allowed to be here -She wasnt allowed to be there

-Teenagers will be allowed to vote at 16 in a few years.

Asking permission and making polite requests:CAN: Can I have a drink? informal


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COULD: Could you pass me the salt, please?

MAY: May I borrow your dictionary, please?

MIGHT:rarely used: Might I sit here? Very formal

EXPRESSING POSSIBILITY

MAY (not) // MIGHT (not) // COULD (not)// CAN:

It could be dangerous to travel alone.

It may not rain tomorrow.

She might win the gold medal in the competition

You can study Biology, too, if you want to.

The 3 of them are used to talk about possible actions in the future or in the present. Both

May and Might express the possibility that something happens in the future, without

being sure. Might is also the past form of May.

The possibility expressed by Could is more remote or uncertain than the one expressed

by Can (We can go on next Friday// We could go on Friday).

CANT signals that we believe or guess that something is impossible: It cant be so

latealready!

MAY/ MIGHT + HAVE + Participle: A guess about something that happened in the

past. We use them when we are not sure because we dont actually know what happened

in the past.

She may have taken the wrong bus.

She might have lived in my town but Im not sure.

COULD + HAVE+ participle: to refer to something possible in the past, but which

didnt happen:

They could have parked nearer the hospital (But they didnt, in fact, they parked

near it)

You could have asked the doctor before taking that medicine.

EXPRESSING CERTAINTY AND DEDUCTION

MUST: we are sure about an action in the present or futureHes broken his leg. It must hurt him a lot

Its 5.30 pm. They must be having dinner, as usual.

CANT/COULDNT + HAVE+ participle: To express certainty that something was

impossible referred to past situations.

She cant have said that! She is very polite!

He couldnt have gone to the concert because he was doing a test.

MUST + HAVE+ participle: Its used to express deduction, a logical conclusion and

certainty referred to the past.


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MODAL VERBS: KEY SUMMARY

MODALS USES Examples

Can

Cant

Cant have + part.

1. general ability in the present or thefuture

2. (informal) request and permission1. Impossibility

I can speak English

Can I use your car?

You cant see the dentist now,sorry.

They cant have eaten that

Could

Couldnt

Couldnt have + part.

1. general ability in the past2. (polite ) request3. Possibility (not certain)4. Suggestion

1. Impossibility ( negative only; pastsituation always)

She could read well when she

was 4.

Could I have a word with you?

The keys could be in the car

We could visit her tonight

I couldnt open the door.

They couldnt have got there

Be able to 1. general ability (=can) ( all tenses)2. specific past ability: managing to do

something despite its difficulty.

Youll be able to drive wellsoon

We were able to find the house

without a map.

May

May not

May have+ part.

1. Possibility in the present or future.2. (formal) request and permission.1. negative possibility (present or

future situation)

1.possibility in the past

It may rain tomorrow

May I call you later?

He may not arrive today

They may have got lost

Might (not)

Might have + part.

1. affirmative and negative probability in the

present, future or past

It might rain tomorrow

Tom might not arrive today

I might have left the towel at

the pool.

Should/ ought to/ had

better (not)

Should/Ought to

Should have +

participle

1. advice2. possibility (90%): prediction

1. criticism; not followed advice

You should/ ought to see a

doctor

He should do well in the exam

She should have finished her

tests in May

Must (present and

future)

Must have + participle

Mustnt

1. obligation felt by the speaker; futureintention

2. strong recommendation3. possibility (99%): deduction in the

present or the past

1. prohibition

I must write a letter to my

aunt.

You must see the doctor

The lights are on. He must be

at home

They must have already

arrived

You mustnt smoke in a

hospital.

Have to ( all tenses)

Dont have to/ Neednt

1. External obligation2. necessity in the future and past1. Lack of obligation, necessity

Shell have to wear glassesI had to leave early.

I dont have to work

tomorrow. Its Sunday.


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