We use must and have to/has to to say that something is necessary!
I have to study because I have an exam tomorrow.
You must go to that restaurant. It’s outstanding.
must or have to?
We use must when the speaker feels that something is necessary. We use have to when the situation makes something necessary.
Sevi: You must stop working so hard. (I am telling you)
Jane to Tom: I have to stop working so hard. (Sevi told me)
I must buy a newspaper. (I want to see the news.)
I have to buy a newspaper. (My boss asked me to buy.)
Negative use of must and have to
We can use don’t have to when something is not necessary.
We use mustn’t to say that something is a bad idea.
Tom’s a millionaire. He doesn’t have to work but he does because he enjoys it.
It is forbidden. You mustn’t smoke here.
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