指示标志是指引驾驶员行驶和停车的标志。
参考答案：对
一列火车第一天晚上10时从连云港出发，第二天5时到达南京，这列火车一共行驶了多少小时？
He went there and there for three days. [ ]
A. three days before; stay
B. for three days; stay
C. before three days; stayed
D. three days ago; stayed
