what/that has happened.为什么是选what?happen后面不是不加宾语嘛?为什么不是that啊!

what/that has happened.为什么是选what?happen后面不是不加宾语嘛?为什么不是that啊! what will happen at that time?对么 what has happen 和what was happen 和what happen有什么区别,它们后面都能加to吗? John has hert his leg.really?____A who did that B How did that happen C What is wrong with him D Why was he so careless What happen what happen what do that happen 和 how do that happen 的区别! __________ proves that my advice is right.A.It will happen that B.That has happenedC.What has happened D.When it happens此题应该怎样选?为什么?及此句的意思 Nobody knew what-----the young man at that moment.(happen) What _____(happen) in the next room at that time? What's the best thing that ever happen to you? what are some things that happen on soup operas? What days does that happen怎么翻译啊?急 it's too bad that Tom has hurt his leg . Really?__________A What's wrong with him?B Who did that C I can't believe it D How did that happen为什么不选A what did that happen?这个句子对么?可不可以理解为一个强调句?how did that happen与why did that happen有什么区别?英语 What do you think ____ (happen)?A to happen B happening C is happened D has happened What happen还是What is happen? What _______(happen) here?There is blood on the floor.这里happen为舍要搭配has,直接填happen不行吗?