Rewrite the sentences with have to,don't have to and mustn't .

1)It isn't necessary for you to come ,but you can if you want to.

 You______________________________________

2)We aren't allowed to stay in the classroom at lunchtime.

 We________________________________________

3)It doesn't matter if you don't finish your dinner.

  You______________________________________

1) you dont have to come, but you can if you want to

2) we mustnt stay in the classroom at launchtime

3)you dont have to finish your dinner