be good at 与be good for有什么区别?

be good at 是＂擅长于.....＂的意思　

be good for是＂对......有利＂的意思

例：I am good at English .

Fruit is good for our health.

be good for: 对...有益处 ,对...适用,有效;值得；适于

eg.

Taking an active part in sports is good for your health.

积极参加运动对你的健康有益.

The ticket is good for one month.

这票一个月内有效。

be good at:擅长于...,善于做...

eg.

I'm good at swimming. 我擅长游泳.