Complete the sentences with the correct modal verb

You couldn't/mustn't/ shouldn't eat so many hamburgers. They're not good for you.

You can't have don't have to/ mustn't study at the weekend, except when you have exams.


You may not/might not/should worry. Everything will be ok.

You don't have to/ might not/ mustn't use your mobile phone in class It can/could/couldn't rain tomorrow.​