This treatment involves scrubbing off the top layer of dead skin.

这种治疗需要把死皮的表层除去。

《牛津词典》

Because of the cold temperatures, the tundra has two layers: top layer, which is called the active layer, is frozen in the winter and spring, but thaws in the summer.

由于寒冷的气温，冻土带有两层：最上面的一层被称为活动层，在冬季和春季被冻结，但在夏季解冻。

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The top layer of skin has to be grafted onto the burns.

表层皮肤必须移植到烧伤处。

《柯林斯英汉双解大词典》

L is for layers.Wearing loose, lightweight clothes, one layer on top of another, is better than wearing a single heavy layer of clothing.

VOA: special.2009.12.23

We changed our name just last week after the acquisition of Top Layer by Corero.

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The top layer contains hundreds of control channels through which pressurized water is pumped.

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Some particles, however, are energetic enough to puncture the top layer and strike the second layer.

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