what has happened?I __ (lose) my key and can't open the door

I wanted to know_to him.为什么填what happened而不是what has happened? what has happened?I have said something unking to my friend.这句为什麽不用 what have happened He asked,What has happened to you?变为间接引语该怎么变是He asked what had happened to me.还是He asked what I had happened . what has happened?为什么用HAS what happened what has happenedwhat happened what has happened 在语义上有什么区别吗 What-------? I --------my key and can't open the door.A.happened;lostB.has happened;lostC.happens;have lostD.has happened;have lost选哪个?为什么? What has happened和What was happened区别 what happened ?和what has happened ?的区别 I want to know what --------- him.A .happened B,has happened to C,is happening D,will happen to What has happened?What has happened?---I have lost my key and can't open the door.为什么不能用What happened?---I lost my key and i can't open the door.两者的区别是什么? I have no idea what has happened to him为什么是同位语从句 what has happened?I __ (lose) my key and can't open the door Tom hasn't come back I wonder what has been happened to him.改错 翻译一下The best part of what has happened was the part i must have missed The best part of what has happened.Was the pan i must have missed. what has happened.这个句式有错吗 what has happened是什么时态的句型 I have no idea what _____while I was asleep .A .has happened Bwas happened C.happened Dhad happened为神马选C呢?为神马ABD错的呢?