托业考试

根据网考网考试中心的统计分析，以下试题在2018/5/27日托业考试习题练习中，答错率较高，为：57%
【单选题】By the time we got back to the office, the clients ______ for the airport already.


A．will have left
B．were left
C．had left
D．would have left