Exercise 9: Đọc và sửa lỗi các câu sai 1. You must do homework at home. 2. People must do not wash the face in the morning. 3. Patients must not drink cold water. 4. You must not watch TV a lot. 5. Students must listen to their teachers. 6. You must take notes during the lessons. 7. We must speak loudly in hospital. 8. Motorbike riders must fasten the seatbelt. 9. You must not wash your hands before lunch. 10. Pupils must not eat in class. 11. Children must not listen to your parents. 12. Students must not break the windows at school. 13. People must take a shower every day. 14. Girls must not eat fruit and vegetables every day. 15. You must eat lots of sweets if you want to lose some weight. 16. The owner must not feed his dog every day. 17. You must brush your teeth five times a day. 18. You must not forget to do your homework regularly. 19. You must wear warm clothes when it is cold outside. 20. Students must not study hard if they want to pass your exam.