be good 后接for可表示“有益的，合適的”，后接to可表示“對友善的”，后接at可表示“精通的，熟練的”。It's good of sb 和It's good for sb 都可接to do sth，但含義不同。前者重在“人”很好，后者重在“事”很好。

be good的用法整理

be good for 對于……來說是好事

例句：Anyway, the news seems to be good for you.

無論如何，這個消息對你來說是個好事。

be good at: 擅長做…

例句：Kids really have to be good at thinking on their feet.

所以孩子們真的是必須擅長獨立思考問題。

be good to: 對…好

例句：Why can't she be good to her sister?

為什么她不能對她姐姐好點？

be good with: 擅長

例句：I think she can be good with Alice.

我想她可以和愛麗絲相處的融洽。

As a politician, you need to be good with words.

作為一名政治家，你必須能說會道。

be good at的例句

1、A good listener must be good at asking questions.一個好的聆聽者應該善于問問題.

2、Be good at harmonize social relationship between all departments, strong ability in communication.擅長協調部分之間人際關系,具有很強的溝通能力.

3、I expect to study in the US one day. Before that day coming, I must be good at English.我期望有天能到美國念書在那天到來之前我必須先將我的英文學好!

4、You could study astronomy, or space engineering, and be good at it.你可以學習天文學,或是空間工程學,可以學的很棒.