一颗恒星其生命的绝大部分处于主序星阶段，在这一阶段它包含一个核心、辐射区和对流区、光球层、色球层和日冕。

A star during most of its life is a main-sequence star, which consists of a core, radiative and convective zones, a photosphere, a chromosphere and a corona.

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这颗恒星曾和太阳一样，是颗“主序星”(“main sequence”)。它通过核聚变燃烧氢，从而产生氦。

The star used to be like the sun, a "main sequence" star that burns hydrogen by nuclear fusion, producing helium.

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在从样本星的色指数（B -V） ，（U -B）和视差得到它们的有效温度和光度之后，我们发现在赫罗图上它们大多数是位于主序带内的。

After deriving their effective temperatures and luminosities from their (B-V), (U-B) colors and parallaxes we find their positions in the HR diagram to be mostly confined to the main sequence.

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