问题补充:
Im afraid I have to go now, for my parents outside.
A. had waited
B. have waited
C. are waiting
D. were waiting
答案:
A. had waited
B. have waited
(答案→)C. are waiting
D. were waiting
解析:句意:现在我想我必须走了,因为我的父母正在外面等着。分析:现在要走,说明父母的动作也正在进行,因此为现在进行时。故选 C