They tried to find out ______ the new train ________. A. how far/ had gone B. how long/ has goneC. how far/ went D. how
问题描述：
They tried to find out ______ the new train ________. A. how far/ had gone B. how long/ has goneC. how far/ went D. how far had/ run告诉我为什么
答
A. 主句用过去时,宾语从句里发生在主句动作之前,用过去完成时