what happened 和WHAT IS HAPPEND的区别

问题描述:

what happened 和WHAT IS HAPPEND的区别
区别在哪里啊?还有个WHAT IS HAPPENING,发生了什么应该是WHAT HAPPEND 那WAHT IS

happen是不及物动词,没有被动语态,因此不可说what is happened.
WHAT IS HAPPENING正在发生什么事情;
WHAT HAPPENED 发生了什么事情.
时态有别.