“MUST NOT” AND “DON’T HAVE TO”

COMMON MISTAKES

“Must not” and “don’t have to” do not mean the same thing.

“Must not” is used to give an instruction that forbids someone from doing something.

“Don’t have to” is used to tell someone that it is not necessary that they do something.

You must not use a calculator during this exam.

(it is against the rules to use a calculator during this exam.)

You don't have to use a calculator, but it might be useful.

(You are allowed to use a calculator, but it is not required.)

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