Have to / Must / Need to
Todd: I have to work today.
Katie: Really. I don’t have to.
Todd: I better go. I need to get ready.
Katie: When do you start?
Todd: At noon, but I have to leave early to beat the traffic.
Katie: Yeah, you need to get going.
Todd: What do you have to do today?
Katie: I have to clean my house.
Todd: Really, it looks clean.
Katie: No, I need to dust, I need to clean the bathroom and I have to do laundry.
Todd: Well, you seem busy, so I must be going.
Katie: Yeah, I need to get started, but call me later.
Todd: We need to pay this bill.
Katie: Why? We don’t have to pay it.
Todd: Yes we do. We must.
Katie: No, it’s not a bill, just a donation.
Todd: But if we don’t pay it, we will look bad.
Katie: No, we won’t. You mustn’t think that way.
Todd: What must we do today?
Katie: We have to mail these letters.
Todd: Anything else?
Katie: Yeah, you need to pick up the kids from school.
Todd: I can’t. I have to work.
Katie: OK, I can do it then. I have to go by the school anyway.
(Q) What do you have to do?
(A) I have to clean my rooms.
(N) I don’t have to finish today.
(Q) Do you have to go?
(A) Yes, I have to. / Yes, I do.
(N) No, I don’t (have to)
not have to = not necessary
You don’t have to come.
You don’t have to read that.
You don’t have to help
(Q) What must we do?
(A) You must try harder,
(N) You mustn’t do that again.
must not = command = do not do!
You mustn’t be late.
You mustn’t make say that!
You mustn’t trust him!
(Q) What do we need to bring?
(A) You need to have a swimsuit.
(N) You don’t need to wear a cap.
(Q) Do we need to show ID?
(A) Yes, you do.
(N) No, you don’t.