The door opened and there .

Tom was a student at this university from 1999 to 2003, ____ he studied very hard and was madeChairman of the Students’ Union.[ ]

Nobody can achieve anything of realsignificance _____ he works very hard.

finishing his homework, he went to play basketball with his classmates.

You can hardly imagine the pleasure of chatting with friends on Wechat (微信).—Really But it ______ cause you much trouble if someone get your personal information.