DOVERE
MUST + VERBO ALL'INFINITO
MUST
You must tidy your room.
She must study history for tomorrow.
MUSTN'T
You mustn't eat in the IT lab.
Mark mustn't be so stubborn.
HAVE TO + VERBO ALL'INFINITO
HAVE/HAS TO
We have to be at school at 8.30 am
Sarah has to clear the table every day after lunch.
DON'T/DOESN'T HAVE TO
We don't have to wear a uniform at school.
My brother doesn't have to take the bus to go to school, he goes on foot.
DO/DOES + sogg. + HAVE TO
Do we have to take our sport bag to school tomorrow?
Does she have to buy so many clothes?