【题目】-How long do you think it will be __________ the Two Sessions （两会）in Beijing come to an end?
-Don't you know they were over on March，17th ？
A. before B. since
C. until D. after
在线课程【答案】A
【解析】句意:——你认为北京的两会还有多久结束？——难道你不知道两会在3月17日结束吗？ It will be +时间段+ before………时间后才……。