它的一生主要经历了两个阶段。

In its whole life, it mainly goes through two stages.

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每个用例必须经历静态的测试来确保它包含清晰而且有利的信息，根据这些信息测试人员可以为指定的测试阶段构建适当的测试用例。

Each use case must undergo static testing to insure it contains clear and beneficial information from which testers can build appropriate test cases for the designated test phases.

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首先，它非常非常老了——它经历过红巨星阶段，这一阶段的恒星会急剧膨胀，吞噬在临近轨道运行的行星。

First, it's really old - past the Red Giant phase, when stars balloon in size and swallow up planets in close orbits.

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