The helping verb have 2. Here, what's is the contraction of what has. This is the present perfect, which is constructed using:
What Really Happened To Sara Underwood? Truth or Fiction
What happened?和what's happening?的区别是什么？what happen?表示发生了什么，用于询问发生了什么事情，通常用于过去的事件或突发情况。而what’s happening?表示正在发生什么，用于
'happend' is a spelling mistake of happened.
接下来让我们看下what happen和what happened的用法区别： 1.词性：what happen是用原形动词happen构成的现在时短语，而what happened是用动词happen的过去式happened构成的过去时短语. The past participle of the main verb the meaning is. What happened 和 what's happened两者的区别： 是问 what happened？只是想知道过去所发生的事情， 而如果用what's happened？则强调对现在的影响。，即想知道过去所发生的什么事导致了说话时. Happened是一个完整的句子，简单过去时来表示过去发的事情。 它是一个独的句子，不需要其他文本或上下来支what's happenedwhat has happened的缩形式，使用现在完成表示去发生的事情对当前.
