这题选什么?为什么?The train had left the station _________ I got the
4个回答

搞懂意思就选得出来了

as soon as 一经...;立即...;一...就...

前后的时态得一致.

by the time ...到...的时候

By the time they get here,we'll have finished the work.

等他们到这里时,我们会已经把工作做完

since,(常用于现在完成时或过去完成时)

此后;从那时到现在

She left school three years ago and has worked as a nurse ever since.

她三年前毕业,从那时起便一直当护士.

after就是在什么之后

原句意思是我到车站的时候火车已经离开了.