GR Modal verbs unit 1

Modal verbs

Obligation, permission and prohibition

Start

Section I

Obligation

Must have to have got to need to,

Must + infinitive

Passengers must fasten their seat belts

Strong obligations which express the authority of the speaker or writer. And it is used for formal rules or laws.

Strong suggestions, advice, recommendations

"You must come to my party. Everyone's coming."

negative form

NEGATIVE FORM

Must not + infinitive

Drivers must not exceed speed limit

Prohibition (negative rules or laws)

negative Strong suggestions, advice, recommendations

"You mustn't blame yourself. It's not your fault."

Have to + infinitive

I have to work late. My boss said so.

Strong obligations which express the authority of a third person. And the speaker wants to show they are not responsible for imposing the obligation.

When reminding someone about a rule or a law

"You have to wear a mask to enter the hospital."

Have got to + infinitive

You've got to stop wasting your money.

IIt's more informal than have to and it's used for direct commands.

for emphasis

The exam is so difficult but I've got to pass it.

negative form

NEGATIVE FORM

Have got not to + infinitive

You don't have to wear a uniform. But you can if you like.

Do not have to + infinitive

Express lack of obligation or necessity. NOT express prohibition.

Need to + infinitive

You need to take these pills

Express necessities, rather than obligations

I think you need to go to the dentist.

negative form

NEGATIVE FORM

There's no lessons tomorrow, I don't need get up early.

Do not need to + infinitive

*needn't get up early

There were no lessons yesterday, I didn't need to get up early.

Did not need to + infinitive

I got up early but there were no lessons yesterday, I needn't have got up early.

Needn't have + past part.

Express lack of obligation or necessity. NOT express prohibition.

Section II

Permission and prohibition

Can / can't Other expressions

Can / Can't + infinitive

Can I use the phone, please?

Express permission in affirmative sentences and questions

Express prohibition in negative sentences

In Spain you can't leave school until the age of 16.

other expressions to express permission

Other ways to express permission

be allowed to + infinitive

Visitors are allowed to use the car park

be permitted to + infinitive

Joseph was permitted to stay up past his bedtime on Saturday night

let + infinitive

My parents let me stay out late at weekends

other expressions to express prohibition

Other ways to express prohibition

be forbidden to + infinitive

not be permitted to + infinitive

not be allowed to + infinitive

Joseph wasn't permitted to stay up past his bedtime on Saturday night

Visitors aren't allowed to use the car park

People are forbidden to smoke on the Underground

be banned from + gerund

be prohibited from + gerund

not let + infinitive

My parents don't let me stay out late at weekends

Children under 16 years of age are prohibited from working

Farmers in Europe will be banned from using particular substances.