sharp
锋利之意
tack
大头针是也
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成语也罢,idioms也罢,都是历经时间的检验所沉淀下来的最形象最有说服力的词汇.
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如大头针一般锋利,就是很快解决问题,就是说一个人很聪明,很灵性等.
(as) sharp as a tack
If someone is as sharp as a tack,they are very clever indeed.
He may be old in years,but he's still as sharp as a tack and knows what he's talking about.