Could, must, need rules examples

Could, must, need

Could

Could is a polite word used to ask for permission or to request something. Friendliness is a wonderful quality to have.

Polite questions

Open the window! (imperative)
Could you open the window, please? (polite question)

Buy me a cup of coffee! (imperative)
Could you buy me a map, please? (polite question)


Could you pass me the tea?
Could we visit London?
Could you help us, please?

Could - something possible in the future

Could: Something is possible in the future (not certain).

I could invite Jane.
He could stay at school.
We could go to the supermarket.

Must - mustn't

Must + infinitive = it is necessary to do something. For past tenses use had to.

positive - must
I must stop the car.
You must stop the car
He / She / It must stop the car.
We must stop the car.
You must stop the car.
They must stop the car.

negative - mustn't
I mustn't stop the car.
You mustn't stop the car
He / She / It mustn't stop the car.
We mustn't stop the car.
You mustn't stop the car.
They mustn't stop the car


Mustn't + infinitive = it is necessary not to do something.

Need - needn't

Need

Need + infinitive = Require something because it is very important.

Needn't

Needn't + infinitive = Require something because it is not very important.

I needn't stop the taxi (because it is not very important to do so).
You needn't stop the taxi.
He / She / It needn't stop the taxi.
We needn't stop the taxi.
You needn't stop the taxi.
They needn't stop the taxi.

Could, mustn't, needn't examples

Could, must, need with explanations, examples and exercises. Change the following sentences into Could, must, need and learn with English online exercises.

Free tutorial Could, must, need. English Could, must, need exercises. English grammar easy to learn.  英语在线练习. Exercícios das aulas de Inglês grátis online, exercícios de vocabulários, gramática inglesa.