问题
选择题
—Do you know about the accident which happened in the center of the city?
—Yes. But it was some time we realized the truth.
A．before
B．when
C．since
D．Until
答案
答案：A
题目分析：句意：－你知道那起发生在市中心的事故吗？－是呀，过了一段时间后我们就了解那个实况。It ＋时间段＋before…“过了一段时间就…”故A正确