what is happening和what happened怎么回答求人指点谢谢

问题描述:

what is happening和what happened怎么回答求人指点谢谢
如题要完整和不完整回答的方式是直接回答一个动名词吗

这个一般不说完整回答不完整回答.
别人问你发生了什么事,你直接回答发生了什么事就好了
what is happening?he is smoking in the bus.
what happened?he came and dropped a book