Срочно!!!! Complete the sentenses with must, have to and their negative

Безотлагательно!!!! Complete the sentenses with must, have to and their negative form
1) i'm really tired. I am glad i .......... Go to university today 2 the sign says that small children..... Stay euth their parents at all times 3) you've only just arrived! ...... you ..... To leave so soon? 4) gymnasts..... Eat too much before a competition