【题目】They were abroad during the months when we were carrying out the investigation, or they _____ toour help.
A. would have come B. could come
C. have come D. had come
在线课程【答案】A
【解析】
试题分析：这里when引导的是定语从句，修饰前面的名词months;根据谓语动词were可知事情发生过去，or后是对过去的虚拟，所以应该用would have done，故选A。句意：在我们进行调查期间他们在国外，要不然的话他们就来帮忙。