用unless 改写句子。
1. We deal with our problems. We can easily become un-happy.
_________________________________________________
2. It is sunny. We won't have a picnic.
_________________________________________________
3. You have finished your homework. You can't play foot-ball.
_________________________________________________
4. The lights turn green. You mustn't cross the road.
_________________________________________________
5. We have enough money. We can't buy the car.
_________________________________________________