一、從詞性用法上比較
　　1.good 只用作形容詞,不用作副詞,其副詞形式用 well.如：
　　He speaks good English.他的英語(yǔ)說(shuō)得好.
　　He speaks English well.他的英語(yǔ)說(shuō)得好.
　　2.well 既可用作副詞,也可用作形容詞.用作形容詞時(shí),其用法很有限,只表示“健康的”“恰當(dāng)?shù)摹被颉傲钊藵M意的”等.如：
　　She is very well.她身體很好.
　　Things are well with us.我們事事如意.
　　注：一般說(shuō)來(lái),well 用作形容詞時(shí),只用作表語(yǔ)而不用作定語(yǔ)(如上例),但在美國(guó)英語(yǔ)中,well 表示“身體健康”時(shí)有時(shí)也可用作定語(yǔ).
　　二、從相關(guān)短語(yǔ)用法上比較
　　be good at 與 do well in：兩者均可表示“擅長(zhǎng)”.如：
　　He is good at languages.他擅長(zhǎng)學(xué)語(yǔ)言.
　　She is good at telling stories.她擅于講故事.
　　They all did very well in the examination.他們這次都考得很不錯(cuò).
　　注：表示擅長(zhǎng)某一學(xué)科時(shí),也可用be good in.如：
　　He is good at [in] maths.他擅長(zhǎng)數(shù)學(xué).
　　2.as good as 與 as well as：用于本義時(shí),兩者均可表示“與……一樣好”,但 good 是形容詞,而 well 是副詞.如：
　　他說(shuō)英語(yǔ)說(shuō)得跟她一樣好.
　　正：He speaks English as well as her.
　　正：His English is as good as hers.
　　但是,用于引申義時(shí),兩者的意思很不相同：as good as 意為“幾乎”“差不多”(=almost),as well as 意為“而且”.如：
　　The work is as good as finished.工作差不多干完了.
　　He as good as said I’m a liar.他無(wú)異于說(shuō)我撒謊.
　　She’s clever as well as beautiful.她不但漂亮,而且聰明.
　　As well as breaking his leg,he hurt his arm.他不但摔斷了腿,而且還傷了胳膊.