What's happening there

问题描述:

What's happening there
A.The cat is swiming in the lake.
B.There is a man siting in front of the door.
C.The boy is eatting a hamburger in class.
D.A girl is jumping off the chair.为什麽选D

前三个选项,都是一种可以持续的动作,无论是游泳,坐着还是吃东西,都可持续一点时间.只有d的动作,快.而且,突发.happen是对事件的提问.一般平常的东西,人们习以为常不会再问了.