【题目】We would have called a taxi yesterday if Harold __________us a ride home.
A.didn't offer
B.wouldn't offer
C.hasn't offered
D.hadn't offered

【答案】D
【解析】句意：昨天如果哈罗德不主动开车送我们回家的话，我们就要打的了。would have done 表明是对过去的虚拟，所以条件句需要用had done。故选D。