1 You dont have to arrive before 9 30
2 Students should not bring any food into the classrooms.
3 You should not eat too much junk food.
4 I would be able to buy a new laptop.
5 You can afford the school trip if you have enough money.
6 You ought to be in bed early if you have an exam.
7 You better start training as soon as possible.
8 You have to wear a helmet if you ride a motorbike.