问题补充：
I am sorry you’ve been waiting so long, but it will still be some time Brain gets back from his holiday.
A. since
B. before
C. till
D. after
答案：
A. since
(答案→)B. before
C. till
D. after
解析：句意：抱歉你等了这么长时间，但是，Brian度假回来还得一段时间。It +be +一段时间+before从句，肯定句翻译为：要多久才….如：It is going to be some time before I recover my full strength. 还要一段时间我才能完全恢复体力。故B正确。
