He is having breakfast 用完成时是不是He has had breakfast?He had had breakfast 是过去完成时，意思是不是很久以前完成的阿？现在完成是不是刚刚完成的？
问题描述：
He is having breakfast 用完成时是不是He has had breakfast?
He had had breakfast 是过去完成时，意思是不是很久以前完成的阿？
现在完成是不是刚刚完成的？
答
He has had breakfast是现在完成时
He had had breakfast是过去完成时
现在完成时表示过去发生的但对现在有影响的动作,可以不用时间状语.也可以和一些表示不定过去的时间状语连用
过去完成时表示过去某一时刻以前已经完成的动作,常由by,before等.主要是宾语或定语从句中常见.状语从句也会用到