问题
选择题
It’s quite a time _____ Liu Xiang was injured in the foot, but we are sure it won’t be long _____ he returns to the track.
A．after; when
B．before; since
C．that; when
D．since; before
答案
答案：D
考查连词用法。句意：自从刘翔在脚部受伤以来有相当一段时间了，但是我们确信不久他就会回到跑道。根据语意应选D。