MODAL VERBSMODAL VERBS

1. They are verbs like can, must, might, etc… which give certain meanings to main verbs.

You smoke. / You shouldn’t smoke. / You mustn’t smoke.

2. They are followed by either:– base form of the verb. I should tell him the truth.– have + past participle form of the verb. I should have told

him the truth.

3. Structure:

(+) We should stay.

(-) We shouldn't stay.

(?) Should we stay?

4. Types of Modal verbs:

OBLIGATION: must / have to / *need

LACK OF OBLIGATION: don’t have to / *needn’t

PROHIBITION: mustn’t

ADVICE: should / *ought to

ABILITY: can / could / *be able to

PERMISSION & REQUEST: can / could / *may* Extra ones

Other situations / modal verbs:

CERTAINTY & LOCAL DEDUCTION: must / can’t / couldn’t

PROBABILITY & POSSIBILITY: can / could / may / might

IMAGINARY SITUATIONS: would

OBLIGATION

(must, have to, *need,)1. OBLIGATION which comes from sb else. It’s a law or a rule and

the speaker can’t change it: HAVE TO

In Britain you have to buy a TV licence every year.

She has to wear a school uniform.

2. OBLIGATION with other verbal tenses: HAVE TO

I ‘ll have to pass those exams to go to university.

We had to leave early.

3. OBLIGATION which comes from the speaker. It isn’t a law or a

rule: MUST

I must call my dad tonight.

Mark is a really nice person. You must meet him. (I recommend this)

*In written rules, MUST is used:

You must write your answers in ink.

* NECESSITY: NEED

You need to tell him the truth.

You need to wear suit for the interview.

LACK OF OBLIGATION

(don’t have to / *needn’t)You don’t have to / needn’t order your meal now.

She doesn’t have to cook dinner tonight.

PROHIBITION

(mustn’t)You mustn’t drink and drive.

ADVICE

(should / *ought to)You should / ought to study more for your exams.

You shouldn’t smoke.

* Ought to rarely seen in negatives or questions.

ABILITY (can, could & *be able to)1. Present: can

Two of my friends can play the guitar.

2. Past: could

When he was a child he could ski well.

Other tenses: be able to

- There was a fire and I was able to escape out (= I managed to escape out) of the room. (specific situation in the past)

- Next week they'll be able to vote. (future)

- We haven't been able to go on holiday this year. (present perfect)

PERMISSION & REQUEST

(can, could & may)Can you help me?

Could you send me your picture?

May I use your phone? (a bit more polite)

CERTAINTY & LOCAL DEDUCTION(must , can’t & couldn't)

1. 100% SURE (CERTAINTY)

They must be an item. I’ve seen them kissing.

(I totally believe this)

2. 100% SURE (STRONG DISBILIEF)

They can’t be an item. They don’t get along.

( I don’t believe it)

They couldn’t be an item. They didn’t get along.

PROBABILITY & POSSIBILITY

(can, could, may & might)

We can invite Jim to the party. (Why not?)

We could / may invite Jim to the party. ( Not so sure…)

We might invite Jim to the party. (Could be but I don’t think so…)

IMAGINARY SITUATIONS: would

It would be nice to buy a car, but I can’t afford it.