-Could you tell me when ----?

问题描述:

-Could you tell me when ----?
-Sorry.I don't know.You can ask the conductor.
A.does the train leave
B.will the train leave
C.the train had left
D.the train leaves
怎么判断时态呢?

选D从主句Could you tell me 用了一般现在时可以看出,问的想现在的情况,故C是错误的.
火车是每天在固定时刻发车的,是一个一般的行为和客观事实,所以用一般现在时表示一般将来时;而不直接用一般将来时,故B错误.而A中不是陈述句的语序,故错误.