An open system, as the name describes, allows mass and energy to freely flow through the boundary.

开系，顾名思义，允许质量和能量自由地,流过它的边界。

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So, there is that kind of a boundary as well, and that is a place where trouble is likely to emerge.

因此,也有那种边界,而边境线上恰恰是最容易发生争端的地方

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It has k2 as the boundary conditions.

它有k2作为限制条件。

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