nhanh giúp mình với 
----- Nội dung dịch tự động từ ảnh -----
III. Choose the correct modal verb to complete the sentences.
1. In a park, you (must / mustn't)
2. On a bus, you (must / mustn't)
3. In a library, students (may / must).
4. In an exam, students (must/mustn't)
walk on the grass.
talk to the driver.
5. To ride a motorbike. students (must/ have to)
6. In a hotel. guests (must / have to)
borrow up to six books.
answer all the questions.
be over 16 years old.
use the exit only in an emergency.