The last time ___ I saw him was last Friday空里应该填that还是when?

问题描述:

The last time ___ I saw him was last Friday
空里应该填that还是when?

that
这是从句,不能用when

The last time that I saw him was last Friday

when,上一次我见他的时候是上周五
主句是the last time was last friday.而i saw him发生的时间是the last time,时间装语的关系,
i saw him in the last time ,用when.