He flattened his hair down with gel.

他用发胶把头发弄平。

《牛津词典》

Today she wore her hair down around her shoulders.

今天她把头发披在了肩上。

《柯林斯英汉双解大词典》

You can let your hair down.

你可以把你的头发放下来。

youdao

So I decided to celebrate, have some fun and let my hair down.

VOA: special.2009.05.03

That hair is now slicked down, there are glasses between him and us.

他的头发梳得很平，有一层玻璃隔在我们和他之间。

耶鲁公开课 - 现代诗歌课程节选

If these 8 million people , would correspond to the number of neurons in the brain, the equivalent of the hair cells that you could get out of a single cochlea would be equivalent to one person walking down 42nd street.

如果这八百万人,相当于大脑中的神经元数量的话，能从一个耳蜗内取出的毛细胞,就好比是,第42大街上的某位行人。

斯坦福公开课 - 7个颠覆你思想的演讲课程节选

Phil Alexander, a computer technician, lets his hair down by writing songs and attending open-mike events.

WSJ: Brits Find Writing a Cheddar Anthem That Isn't Cheesy Isn't Easy

Women wore their hair down (often with deep side parts) and kept their makeup minimal.

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More than at mixed-gender conferences, same-sex events offer a chance for women to let their hair down.

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