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Modals: Prohibition with Must Not

Modals can be used to show prohibition.

must not is used to show prohibition.


Must not is used to show prohibition. This means that something isn't permitted or allowed.

  • He must not open his presents before Christmas morning.
  • You must not stay out too late at night.
  • We must not abuse our superpowers.

Must not is mustn't when speaking. The t in must is NOT pronounced when it is contracted.

  • He mustn't open his presents before Christmas morning.
  • You mustn't stay out too late at night.
  • We mustn't abuse our superpowers.

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