Mustn't or Don't Have to?

Quiz

Which of the following sentences is incorrect?
  1. You mustn't smoke in here.
  2. She doesn't have to come if she wants to stay home.
  3. They mustn't donate if they prefer not to.
  4. We really don't have to talk about it.

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Quiz

Answer

The incorrect sentence is sentence number three:
  • They mustn't donate if they prefer not to.


Why?

This sentence means to say that the choice is theirs. They can donate if they wish, and if they don't want to – it's ok too.
"Mustn't" turns the sentence into a command, so it's incorrect.


The same sentence corrected

To correct the sentence, we could say:
  • They don't have to donate if they prefer not to.


See also:

Synonyms and Antonyms

English Vocabulary Activities

Building Vocabulary and Some Common Mistakes

English Vocabulary Quizzes

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