从词性用法上比较good只用作形容词,不用作副词,其副词形式用well。well既可用作副词,也可用作形容词。用作形容词时,其用法很有限,只表示“健康的”“恰当的”或“令人满意的”等。
从相关短语用法上比较
be good at 与 do well in:两者均可表示“擅长”。如:
He is good at languages. 他擅长学语言。
She is good at telling stories. 她擅于讲故事。
They all did very well in the examination. 他们这次都考得很不错。
注:表示擅长某一学科时,也可用be good in。如:
He is good at [in] maths. 他擅长数学。
2. as good as 与 as well as:用于本义时,两者均可表示“与……一样好”,但 good 是形容词,而 well 是副词。如:
他说英语说得跟她一样好。
正:He speaks English as well as her.
正:His English is as good as hers.
但是,用于引申义时,两者的意思很不相同:as good as 意为“几乎”“差不多”(=almost),as well as 意为“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. 他无异于说我撒谎。
She’s clever as well as beautiful. 她不但漂亮,而且聪明。
As well as breaking his leg, he hurt his arm. 他不但摔断了腿, 而且还伤了胳膊。