题干
一 Sam, come downstairs, please. I need your help.
一 Sorry, mum. I on the phone.
A：am talking
B：talked
C：was talking
答案(点此获取答案解析）
A
一 Sam, come downstairs, please. I need your help.
一 Sorry, mum. I on the phone.
A：am talking
B：talked
C：was talking
