Sorry!Ididn’tnoticeyouenteringtheroombecauseI

問題詳情：

 Sorry! I didn’t notice you entering the room because I ______ a phone call.

A. answered   B. had answered    C. was answering  D. has been answering

【回答】

C

知識點：過去進行時及其被動式

題型：選擇題