I s the heavy rain harmful _the crops?A.for B.atI s the heavy rain harmful _the crops?A.for B.at C.with D.to答案是D为什么不选A呢?be harmful to与be harmful for有什么区别?

I s the heavy rain harmful _the crops?A.for B.atI s the heavy rain harmful _the crops?A.for B.at C.with D.to答案是D为什么不选A呢?be harmful to与be harmful for有什么区别?
I s the heavy rain harmful _the crops?A.for B.at
I s the heavy rain harmful _the crops?
A.for B.at C.with D.to
答案是D为什么不选A呢?be harmful to与be harmful for有什么区别?

I s the heavy rain harmful _the crops?A.for B.atI s the heavy rain harmful _the crops?A.for B.at C.with D.to答案是D为什么不选A呢?be harmful to与be harmful for有什么区别?
to 对… 有害:
固定搭配呗,记住就是；
再如：
pesticides that are harmful to the environment
对环境有害的杀虫剂
It is conspicuous that smoking is harmful to health.
很明显,抽烟对健康有害.