When I swim fast breast stroke, I try to picture that I can almost dig into a cross position with body flat on the water and my arms are a 180 degree.

当我快速蛙泳时，我总是能展现一个十字姿态：身躯平躺在水中，手臂展开180度。

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This paper presents a finite-volume method for flow characteristics simulation in a combustion chamber with a flat-topped piston during the compression stroke.

本文提出压缩冲程期间计算平顶活塞燃烧室流动特性摸拟的有限容积法。

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The framework of the long-stroke pumping unit with compound crown sheave consists of a flat frame with four columns, two cantilever beams and two back legs.

复合天轮式长冲程抽油机主架由四柱扁框架、两个悬臂梁和两个后支腿组成。

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