Modal verbs (i) must have toPresentation Transcript
MODAL VERBS (I): Must, have to, should (obligation) p. 134
Must vs. Have to
Both indicate obligation, but there’s a little difference.
It’s getting late. I must go now obligation from the speaker .
It’s getting late. My mum told me I have to be at home at 9. obligation from another person .
Must is more common for specific (on one occasion) or personal obligations .
I must turn off my mobile. The battery is dying (specific occasion; it’s my own decision).
Have to is more common for general , external obligations , like rules and laws.
You have to turn off your mobile on a plane. (rule)
You have to wear a seatbelt in the car. Do you have to work on Satudays? I had to wear a uniform when I was at school. I must go to bed. I’m exhausted. I must remember to phone her tomorrow – it’s her birthday. FROM ANOTHER PERSON FROM THE SPEAKER OBLIGATION
In spoken English, especially in the USA, people say got to (or gotta ) instead of have to.
I gotta go now. It’s getting late.
I got to study – I have an exam tomorrow.
Must is a modal verb. The only forms are must and mustn’t.
Must , as ALL MODALS , is ALWAYS followed by infinitive WITHOUT TO!!!
You can also have to and must for strong recommendations.
You must see “The Queen”, it’s a fantastic film.
You have to listen to this song – I love it!
No obligation/necessity: don’t have to.
You don’t have to come to the party if you don’t want to.
You don’t have to pay for the photocopies, they are free.
Don’t have to and mustn’t are completely different. Compare
You mustn’t smoke inside a hospital. It’s forbbiden. ( It’s the law )
You mustn’t drink and drive.
You don’t have to drive to the party, I’ll pick you up. (You can drive if you want, but it is not necessary ).
You can use can’t or not allowed to instead of mustn’t.