must, mustn't, and needn't
Complete the sentences. Use the present perfect form of the verbs in brackets.
Teachers ___wear suits for work, but their clothes must be neat and clean. Student ___suse their mobile phones during the lessons. You ___arrive on time for lessons. It's important not to be late. You ___eat lunch in the school canteen. Some students prefer to go home for lunch. Students and teachers ___be polite to each other. You ___buy a coursebook, your teacher will give you one. You ___eat or drink in any of the classrooms. Students ___take an exam at the end of the year.This shows how much they have learnt.