Aalter offered us a lift when he was leaving the office ,but our work__,we refused the offer.

问题描述:

Aalter offered us a lift when he was leaving the office ,but our work__,we refused the offer.
A.had not been finished B.not being finished
选择什么?为什么选它?又为什么不选另一个?呵呵

A.had not been finished
过去完成时态的被动语态