Fill the missing modal verbs (must / mustn’t) 1. Students do homework. 2. Students fight at school. 3. Students be on time. 4. Students listen to the teacher. 5. Students draw or write on the desks. 6. Students use phones. 7. Students wear school uniform. 8. Students make a noise during the lesson. 9. Students raise a hand for answer. 10. Students chew a gum.