Could, mustn't, needn't exercises
Could is a polite word used to ask for permission or to request something.
Could you pass me the tea?
Must - mustn't
Must + infinitive = it is necessary to do something.
positive - must
negative - mustn't
Mustn't + infinitive = it is necessary not to do something.
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).
English Could, must, need exercises
Could, must, need with free online exercises, examples and sentences, questions and Could, must, need negative sentences.
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