The technique of expression is unlimited, but must is a flat surface work.

表现手法不限，但必须是平面作品。

youdao

You need an even surface to work on.

你需要有个平面在上面工作。

《牛津词典》

It can simply be left on the work surface.

把它放在操作台面上就行了。

《柯林斯英汉双解大词典》

Embroidery work involves using colored yarn and a needle to create designs on the surface of cloth.

VOA: special.2009.11.04

It will surface back up in another piece of work or another idea at some point in your life.

在某个时刻，旧点子会以另一种形式重新出现,或者另一个想法在会出现在你的生活中。

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So, it doesn't need to bind to a receptor on the surface of the cell in order to work because the molecule can actually enter the cell directly.

所以无需与细胞表面受体相结合来起效,因为这些分子能直接进入细胞

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He suggests training on a slide board in socks sliding from side to side on the slick surface to work the thigh muscles.

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Many child changing stations are inside the female lavatories so I had to carry a tarp and often change him one-handed when there was no surface to work with.

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Where the Surface RT and Surface Pro both struggle is their dependence on, ironically enough, the proper work surface.

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