If you want to be healthy ,why ___enough exercise?

问题描述:

If you want to be healthy ,why ___enough exercise?
A.not have B.do not have C.not having D.do you not have

选 A
如果你想健康,为何不做足够的运动.
这里是考察why not do sth,和why don't you do sth句型.
表示建议,为何不做某事.