Read these sentences and write another variant of these sentences with the modal verbs (mustn’t, must, can’t, have to, don’t have to, needn’t). You shouldn't change the meaning of these sentences. Don’t forget about full stops.
Example 0. You have to keep the room tidy.
Answer 0. You must keep the room tidy.
1. You mustn't cheat in an exam.
2. You can’t turn the music too loud.
3. You needn’t buy this flat.