I must (do something) = I need to do it:
* I'm very hungry. I must eat something.
* It's fantastic film. You must see it.
* The window are very dirty. We must clean them.
For the past (yesterday / last week etc..), We use had to.. (not must):
* I was very hungry. I had to eat something. (not I must eat).
* We had to walk home last night. There were no buses. (not We must walk).
mustn't (= must not)
I mustn't (do something) = it is necessary not to do it, it is the wrong thing to do:
* I must go. I mustn't be late.
* I mustn't forget to phone Chris. (= I must remember to phone her)
* Be happy! You mustn't be sad. (= don't be sad)
* You mustn't touch the pictures. (= don't touch the pictures)
Don't need to:
I don't need (to do something) = it is not necessary:
* I don't need to go yet. I can stay a little longer.
* You don't need to shout. I can hear you OK.
You can also say don't have to...
* I don't have to go yet. I can stay a little longer.
Compare don't need to and must:
* You don't need to go. You can stay here if you want.
* You mustn't go. You must stay here.
Make sentences. Use must + verb:
1. I'm very hungry. I must eat something.
2. Marilyn is a very interesting person. You must meet her.
3. My hands are dirty. I must wash them.
4. You must learn to drive. It will be very useful.
5. I must go shopping. I need to buy some food.
6. The game tomorrow is very important for us. We must win.
7. You can't always have things immediately. You must be patient.
Make sentences. Use I must or I had to.
1. I had to walk home last night. There were no buses.
2. It's late I must go now.
3. I don't usually work on Saturdays. but last Saturday I had to work.
4. I must get up early tomorrow. I have a lot to do.
5. I came here by train. The train was full and I had to stand all the way.
6. I was nearly late for my appointment this morning.
I had to run ti get there on time.
7. I forgot to phone David yesterday. I must phone him later today.
Make the sentences. Use mustn't or don't need to + verb:
1. I don't need to go home yet. I can stay a little longer.
2. We have a lot of time. We don't need to rush.
3. Keep these papers in a safe place. You mustn't lose them.
4. I'm not ready yet, but you don't need to wait for me.
You can go now and I will come later.
5. We mustn't forget to turn off the lights before we leave.
6. I must contact David, but I don't need to phone him - I can send him an email.
Make sentences with answers with the same meaning:
1. We can leave the meeting early = We don't need to stay until the end.
2. We must leave the meeting early = We can't stay until the end.
3. We mustn't leave the meeting early = We must stay until the end.
4. We had to leave the meeting early = We couldn't stay until the end.
5. We don't need to leave the meeting early = We can stay until the end.
Make sentences. Use must / mustn't / had to / don't need to:
1. You don't need to go. You can stay here if you want.
2. It's a fantastic film. You must see it.
3. The restaurant won't be busy tonight. We don't need to reserve a table.
4. I was very busy last week. I had to work every evening.
5. I want to know what happened. You must tell me.
6. I don't want Sue to know what happened. You mustn't tell her.
7. I must go now or I will be late for my appointment.
8. Why were you so late? I had to wait half an hour for a bus.
9. We don't need to decide now. We can decide late.
10. It's Lisa's birthday next week. I mustn't forget to buy her a present.
