1.You must wear a seatbealt at all times whaen yyou are travelling by car.
2.You must be eighteen to vote in the UK. must be respectful to other srivers at all times
4. she must study very hard for getting high scores.
5.he must be quiet in the library. mustn't copy during the exams.
7.he mustn't drive drive without a licence.
8.he mustn't use a mobile phone while you are driving.
9. you mustn't drive faster than the speed limit. musn't smoke in a petrol station. have to arrive on time every day.
12.he have to have a password for internet acces.
13.students have to catch up with their schoolwork if they have missed a class.
14.she have to be back at 10 o'clock
15.I have to have enough money for eating in a expensive restaurant.
16. you don't have to go to school on sundays.
17.I don't have to get up early on saturdays.
18.she don't have to show your library card to return a book.
19.she don't have to call a taxi.
20.he don't have to take part in after-school activities.

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