what happened?语法对吗

what happened?语法对吗 what happened这个句子对吗 为什么 What is happened?happened是形容词、名词还是动词?学语法乱了乱了 what had happened happened again,这句语法对么,或者怎样改, what happened what has happened what brought it about?是什么意思,语法对吗 What a weather day! 语法对吗? Next,what should i do?语法对吗 what happened/what was happened/what is happened/what happen what happened,what will never change 这句话符合语法吗? What had happened?What had happened?What had happened? 是What happened 还是what’s happened