what happened和what is going on 的区别

what happened和what is going on 的区别
主要在于时态
what is going?问的是正在发生的事情
what happened?问的是已经发生的事情(一般就是刚刚过去的)
口语中都比较常用，意思为，怎么了？发生了什么？

　　what happened发生什么事了；发生了什么事；怎么了
　　例句：
　　1.He did not give any importance to what happened to himself.
　　他从来不把自己的安危看得那样重。

　　2.He decided to do all he could to produce a still higher vacuum and find out whathappened then.
　　他决心尽一切力量造成更高的真空度，看看会有什么景象发生。

　　3."Don't talk like a fool, " I said. "Besides, what happened to me is supposed to be funny. I never think about it. "
　　“别说傻话了，”我说。“而且，对我自己的遭遇，我总是一笑置之，我从来不去想它。”
　　what is going on怎么回事；发生了什么事；怎么一回事
　　例句：
　　1.What is going on with you that you feel so happy to be around your kids?
　　什么会使你觉得孩子在你周围很幸福？

　　2.By objectifying his thoughts in the medium of language, he gets a chance to seewhat is going on in his mind.
　　通过语言来表达思想，他看到了自己头脑中发生的一切。

　　3.The flipside of his benign attitude to staff is his determination to know what isgoing on at the company at all times.
　　在他对待员工态度温和的另一面，是他对公司状况了如指掌的决心。

这里be going用到的是现在进行时态表将来，很多词，比如go,come,leave,arrive都有这种用法
例句，The train is coming.火车即将到来
what is going on? 一般将来时，是说接下来要将要干什么 是将来的事
what happened 普通的一般过去时，发生了什么事 是过去的事
两者在时态上市完全不一样的

前者是发生了什么 ，
后者是正在进行或发生的事