What's the difference between "must not" and "don't have to"?
Must not = mustn't = this is not allowed / this is against the rules.
"You mustn't drive further."
- "You mustn't smoke in here."
- "Kids must not drive."
- "You must not cross the road when there is a red light."
Don't Have To
Don't have to = this is not necessary / it's okay not to do it.
"You don't have to buy from him."
- "You can come with us to the trip, but you don't have to."
- "She doesn't have to work there. She can quit."
- "I don't have to agree with everything he says."
In summary, "must not" is a command not to do something, and "don't have to" leaves the choiceto you.
Which of the following sentences is incorrect?
- You mustn't smoke in here.
- She doesn't have to come if she wants to stay home.
- They mustn't donate if they prefer not to.
- We really don't have to talk about it.