if i had done与if i would have done的区别，还有我以前并没有见过

Question

if i had done与if i would have done的区别，还有我以前并没有见过后者！哪位高人帮我讲讲谢谢啦！

Answer 1

是说以前如果想/要/会干什么的话（实际没想过，不会），if i would have killed u, u would be dead.
如果我以前要/会/想杀你的话，你现在已经死了。
if had 是说 假设做了的话，

Answer 2

用于虚拟语气时，
if I had done是对发生在过去动作的虚拟；
IfI would have done是对将来完成时的虚拟(will have done)本回答被网友采纳