Theambulancewasjustarriving,foraworker,who

问题详情：

The ambulance was just arriving, for a worker, who ______ the window on the second floor, fell off the window.

A．had been repairing                                     B．was repairing

C．has been repairing                                      D．would be repairing

【回答】

A

【解析】

考查时态。根据句意可知，工人修理窗户发生在掉落下来之前，即过去的过去，过去完成时

知识点：过去完成进行时

题型：选择题