how long __each other before the __married?

问题描述:

how long __each other before the __married?
---how long ___ each other before they ___ married
--- For about a year.
a.have they known ; get b.had they known ; got
为什么要用b不用a 怎么理解的?
那里看的出都是过去发生的动作?

首先,他们应该已经结了婚了,所以get married 应用过去时got
其次,这个句子说的是结婚以前,是过去的过去,所以用过去完成时