What happened: 还是what's happened

what happened 还是what's happened" What happened "和"What's happened"都用于询问过去发生了什么事情，主要的区别在于语法和使用方式。" What happened "是一个过去时态的简单 happened的用法如下： 1.happened是 不及物动词,作“发生”解时,可指偶然的事故,也可指有计划或无计划发生的事。一般以事件、环境、形势等作主语,表示“某人发生某事”时,须以介词to引出“某人”。 2.作“碰巧”解时,其后须接 动词不定式 构成复合谓语,可由 人称代词 或无人称代词it作主语。与if连用则可使语气委婉。 3.happened也可如be般用于存在句中,其时态须与其后的主语 ... 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。 It's happened Contrary to what @ZhyAnn wrote ("it's happened is incorrect and never used"), in fact "it's happened " is acceptable and often used. The Corpus of Contermpoary American English shows 1047 instances of its use. The British National Corpus shows its use at a similar rate per 100,000 words. The classic texts at Gutenberg.org show it 187 times. "It's happened " is typically (but not necessarily) a recent report of something that has just now, just recently, happened . (Say, for ...