What happened,Tom?---I lost my key __ the door.A toB ofC forD with应该选哪个?为什么?

what happened to Tom's car?变为同义句 what happened to Tom yesterday ___ ____ ___ ___ Tom yesterday改为同义句 Tom happened an accident. To his credit,Tom never told the enemy exactly what had happened.happened前面可以加had吗?不是一般都直接写成what happened. -What happened with you yesterday ,Tom?-I lose my purse.改病句 Tom hasn't come back I wonder what has been happened to him.改错 What had happened?What had happened?What had happened? 是What happened 还是what’s happened what happened=what's happened吗? what happened to 和what happened Tom,What _ you in class?---I fell asleep.A.is happening on B.happened on C.happened to D.isTom,What_youinclass?---I fellasleep.A.is happening on B.happened on C.happened to D.is happening to what happened at last? what happened on What Happened to Us what happened then Dear,what happened to what happened to she what happened to him?