Ex.5
1. X: Doctor, do I have to stay in bed all the time?
Y: No, but you have to keep warm. So please don't go outdoors.
2. My brother doesn't have to get up early. He always starts classes at 9.00 a.m.
3. I don't think Jane is training hard enough. She has to try harder if she wants to win the next game.
4. We've got plenty of time. We don't have to hurry.
