The eldest said, "it is nothing but a nail in the wall."

大女儿说：“这只不过是墙上的一颗钉子。”

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She says she'll come, but I can't nail her down to a specific time.

她说要来，但我无法让她敲定具体什么时候来。

《牛津词典》

It is smaller than a finger-nail, but it can store more than a million "bits" of information.

它比指甲还小，但却能存储100多万比特的信息。

youdao

"A little layer of rubber -- it will protect you from a stone or a glass, but a nail could puncture that, " Thompson said.

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The objective is a verbal nail, but you need a visual hammer to accomplish your objective.

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Yes, they'd have to go buy a bullet (and a nail), but it's still a way around a background check.

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