Modals - 'must' and 'mustn't'

Do you want to practise using the modals must and mustn't in English?


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Modals – 'must' and 'mustn't'

We can use must and mustn't to talk about rules and obligations.

I must do my homework. We must wear our school uniform.
You mustn't be late for class. We mustn't speak when the teacher's speaking.

How to use them

Must means 'Do it!' If you don't do it, you will be in trouble.

You must listen to the teacher.

Mustn't means 'Don't do it!' If you do it, you will be in trouble.

We mustn't forget our books.

Use the infinitive without to after must and mustn't.

Children must respect their parents.
Parents must take care of their children.
You mustn't shout in the library.

Average: 4.4 (20 votes)

Submitted by LovelyDungeon9999 on Wed, 10/05/2023 - 11:10


Mustn't mean do not do and must mean you have to do. I'll give you
some examples.
You must listen to the teacher because if you don't, you don't know what to do.
You must wear the correct school uniform.
You mustn't be rude to your friends.
You mustn't shout in someone's ear.

Submitted by DJMagicPuppy on Thu, 27/08/2020 - 15:01

That's really easy. I love this web!!!! Is the best!!!!!!

Submitted by SapphireFire3000 on Tue, 31/03/2020 - 22:30

the second one is too easy

Submitted by SapphireFire3000 on Tue, 31/03/2020 - 22:28

first game is not working

Hi SapphireFire3000,

Unfortunately some of our games don't work on mobile phones or tablets.

If you're using a computer you may need to update your version of Flash or enable it in your browser. Can you ask an adult to help you? If you still have a problem, please ask them to email us.


Best wishes,


LearnEnglish Kids team

English courses for children aged 6-17

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