By the time you get to the airport,she_ for New Zealand.

问题描述:

By the time you get to the airport,she_ for New Zealand.
A.would be leaving B.has already left
C.is leaving D.will have left
为什么不选B

因为By the time you get to the airport用的是现在时,说明这件事情还没有发生,否则应该用完成时,所以后面也应该用将来时.