at that moment 用于什么时态?

过去进行时
类似,at the moment当前,常用现在进行时.
what were you doing at that moment?
He got home at that moment?_get是点动词,本身就是一瞬间,怎么可能用进行?
其实,过去时本身,got,也有动作在当时发生的意思．