Archibaid was a whale at fishing in his young days.
　　
（误译）阿奇比德年轻时捕鱼捕到了一条鲸鱼。
（正译）阿奇比德年轻时擅长捕鱼。

a whale at 热心于……的人，善于……的人

Our monitor is a regular whale at work.
我们的班长是个一贯勤勤垦垦工作的人。

He is a whale at ping pong.
他是乒乓界的出众人物。

其他擅长说法：

1. be good at

Be good at English, both oral and written.
良好的英语书写与表达能力。

A good listener must be good at asking questions.
一个好的聆听者应该善于问问题。

Be positive and proactive; be good at learning and thinking.
乐观的心态，积极向上，勤学好问，善于思考；

2. be expert in

Be expert in education and publications.
对教育、出版均有研究。

I hope I will be an expert in this field.
我希望在未来成为这方面的专家。

He is said to be expert in English speech.
据说，他擅长用英语作演说。

3. be skilled in

An army commander must be skilled in tactics.
一名军事指挥官必须对战术很老练。

writers must be skilled in the art of definition.
词书编纂者必须精于给词语下定义的技巧。

Dictionary writer must be skilled in the art of definition.
词书编纂者必须精于给词语下定义的技巧。