1、Could you make sure---------- ? A 、when the train leaves B、if the train had left C······1、Could you make sure ?A 、when the train leaves B、if the train had left C、when the train would leave D、where has the bus gone

问题描述:

1、Could you make sure---------- ? A 、when the train leaves B、if the train had left C······
1、Could you make sure ?
A 、when the train leaves B、if the train had left
C、when the train would leave D、where has the bus gone

A.这是一个宾语从句的疑问句。从句用一般现在时。

选A
注意 Could you 是现在时,后面不用过去完成和过去将来

A.
这里could表示委婉的语气,并不表示过去式,因此选择A.
B中had left 没有使用过去完成时的道理,C would应该是will,D没有这种说法.