用适当的并列连词填空
1.It rained,_____ the football match was put off.
2.____ he was ill,he managed to look happy.
3.Work hard,_____ you will catch up with your classmates.
4.Work hard,_____ you will fall behind.
5.The sun is not a very big star,_____ it makes our lives possible.
6._____ ______ did the students dance,_____ ______ their teachers sang.
7.The girl likes dancing tea,_____ her twin sister prefers to coffee.