Drawing a straight line on a piece of stone and make the surface curved naturally on one side, the curved surface sprawl across the other three edges.

在一块石板上刻画一条直线，在线的一侧做成起伏不定的自然曲面，曲面向另外三边自由蔓延。

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The curved upper surface of a nonturbulent liquid in a container that is concave if the liquid wets the container walls.

弯月面容器中之静止液体的弯曲上表面，如果液体浸润了容器壁，那么弯曲面呈凹状。

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If the universe's space-time is positively curved, like the surface of a sphere, parallel beams would come together.

如果宇宙的时空像球体表面一样正向弯曲，平行的光线就会交合在一起。

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"Well,one of the things that's interesting about these flexible sheets is that they can be curved, so you could imagine putting them in unconventional forms, like on the surface of a vehicle or something like that, where you don't have a flat surface."

VOA: standard.2010.02.19

In particular, the processes by which the circuit pattern is first projected on to a chip's surface lithographically, and then etched on to it chemically, will need to be altered to take account of the fact that the surface is curved.

ECONOMIST: Semiconductors

There was no visible wood grain in the print, and its shape indicated it was taken from a curved surface, not a flat one.

BBC: Fingerprint evidence is fallible

The projection provided a solution to a puzzle that had troubled mapmakers since the world was recognized as a sphere: How does one represent the curved surface of the globe on a flat chart?

WSJ: Lost in Our Maps: A History of Cartographic Catastrophes