I think time is like the water flows to the sea, like a stream does not go back, so we should cherish the time.

我想时光就像流入大海里的水一样，是流不回去，所以我们要珍惜时间。

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For production analysis, the concentration of the tracers that flows back to the surface over time can determine the effectiveness of each stage.

在生产分析中，不同时刻下随着产出液回流到地面的示踪剂浓度可用于确定每个生产层段的有效性。

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