Theambulancewasjustarriving,foraworker,who

問題詳情：

 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

知識點：過去完成時及其被動式

題型：選擇題