Some galaxies occur alone or in pairs, but they are more often parts of larger associations known as groups, clusters, and superclusters.

一些星系单独出现或成对出现，但它们更经常以叫做星群、星团和超级星团的较大的星协的组成部分来出现。

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Some galaxies occur alone or in pairs, but they are more often parts of larger associations known as groups, clusters, and superclusters.

一些星系单独出现或成对出现，但它们更经常以叫做星群、星团和超级星团的较大的星协的组成部分来出现。

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