Can you tell me the difference between Musn't ,Don't have to and haven't got to?
There's an important distinction between the first and the others. Not only is it spelt wrong ( - the first t in "mustn't" is silent), but it is also a prohibition - you must not do it (doing it is something that you are obliged to avoid).
'Don't have to' and 'haven't got to' both admit the possibility of doing it; there is just no requirement to - you can if you like.
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