沒(méi)有what is happened,happen無(wú)被動(dòng)語(yǔ)態(tài),是what has happened,可能到現(xiàn)在仍在持續(xù)；what happened是怎么了,發(fā)生了什么的意思,強(qiáng)調(diào)已經(jīng)發(fā)生并結(jié)束,是過(guò)去時(shí)

what up不規(guī)范,只是美劇里有人的口頭禪,可理解為怎么了；what's up就是問(wèn)對(duì)方近來(lái)如何,有點(diǎn)像中文里的“最近怎樣”,通常沒(méi)什么事就會(huì)回答"Not much"或者"Nothing".