--- Did you telephone Uncle Sam our plan for the Christmas holidays on his farm?

--- Yes, he was happy about our arrival, and he eagerly asked when ______.

A．has we arrived

B．we had arrived

C．were we arriving

D．we were arriving

账户的基本结构可以简称为（）。

A.“左右账户”

B.“一字账户”

C.“丁字账户”

D.“土字账户”