The key to exercise solutions in chapter Progress Check 2 for the textbook On Screen B1+/B2 - Student's Book with authors Virginia Evans and Jenny Dooley from Express Publishing
Question
Rewrite the sentences using an appropriate modal verb.
Answer
You mustn’t take pictures.
You needn’t / don’t have to feed the cats.
Students have to pick up their rubbish.
You should / ought to listen without interrupting.