问题
选择题
Mike didn’t notice Alice entering his room. He ____ a phone call.
A．answered
B．has answered
C．was answering
D．is answering
答案
答案：C
本句的语义环境为：He ___a phone call when Alice entered his room表示过去某一时间正在发生.进行的动作，用过去进行时。故选C