I haven’t seen you for a couple of days . What have you been up ?A. in B. toC. with D. for

问题补充：

I haven’t seen you for a couple of days . What have you been up ?

A. in

B. to

C. with

D. for

答案：

A. in

B. to

C. with

D. for

解析：be to 在干什么。好久未见了，他在忙些什么？故选B。