()()()()()(()())(((()

3 1)mustn't finish 2)must remember 3)musnt't be 4)must give 5) must buy 6)must write 7) musnt't eat 8) wash
4 1)I must wash my hands before lunch.
2)I must help my little sister and brother.
3)I musnt't her bad marks in the school
4)I must clean my room on the holidays
5)I mustn't be a bad child for my mother and father