II. Remove the wrong variant of the modal verb or their equivalent. 1. You are not to / mustn't sleep at lectures. It's impolite. 2. I live in the suburbs. I must / have to take a train every day. 3. You may / can stay here as long as you can. I don't mind. 4. Even if you want to see him you shouldn't / needn't call on him now. 5. It's not your fault. You shouldn't / needn't apologize. 6. Alice can't ride well. She must have had / could have had little practice. 7. Carrie expects them today. They mustn't have gone / can't have gone to a show. 8. Can they have forgotten / may they have forgotten about the party? 9. I don't know where they are. They can be / may be on holiday in Switzerland. 10. It's so hot. The ice-cream should have melted / must have melted.