They're good customers who always pay on the nail.

他们是好主顾，付账从不耽搁。

《牛津词典》

Vertical ridges on the nail mean a possible iron deficiency.

指甲上的垂脊意味着可能缺铁

youdao

He proceeded to hang his coat and hat on the hook that he had drawn in chalk (really on the nail, of course).

随后便将自己的外衣和帽子挂在了那个粉笔画的衣钩上(其实当然是挂在了那钉子上)。

youdao

When you hit the nail on the head,exactly on its top, it goes into the wood perfectly.

VOA: special.2009.09.20

And to give you a size perspective, that is about the size of my pinky finger nail, 4 mm on the side.

这个芯片，有我的手指甲那么大，边长4毫米。

斯坦福公开课 - 7个颠覆你思想的演讲课程节选

And when someone says your words or actions hit the nail on the head, he means what you said or did was exactly right.

VOA: special.2009.09.20

The Baltic states pay cash on the nail for their gas, and offer the Russian oil industry its most efficient export routes.

ECONOMIST: Still most awkward partners

In deciding to attack the Abu Sayyaf, Mr Estrada hit the nail on the head.

ECONOMIST: Estrada��s risky strategy

One of the case studies she shared with me really seemed to hit the nail on the head.

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