1. Let us ask mother. She must know his address. 2. You mustn't drink cold water if you don’t want to fall ill. 3. Can you help me? — I am afraid not. 4. You mustn't interrupt me when I am speaking. 5. Pupils mustn't talk during the lesson. 6. It may rain, take your raincoat. 7. My father must be at his office now as it is 8 o’clock already. 8. Can I switch on the radio? — Yes, you can. . 9. May (can) I smoke here? — No, you may not (can not). 10. You can take my pencil for a moment. 11. I can't finish this work today. I am tired.
