如内部区域质量增加，它的引力变得更大-或以相对论的语言，附近的空间变得逐渐地不成形。

As the mass inside that region increases, its gravity becomes stronger - or, in the language of relativity, the space around it becomes increasingly deformed.

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因为这些星系的质量分布在更大的区域，它们每单位体积的恒星数量比传统星系要少得多。

Because these galaxies' mass is spread out over larger areas, they have far fewer stars per unit volume than do conventional galaxies.

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这些区域确实改善了空气质量，而且科学表明，这意味着切实的健康收益——心脏病、中风和早产发病率降低，癌症、痴呆和哮喘等疾病的减少。

The zones do deliver some improvements to air quality, and the science tells us that means real health benefits—fewer heart attacks, strokes and premature births, less cancer, dementia and asthma.

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The same nations and the short life expectancy of birth probably the lowest quality of life in other areas.

这一数字在下降，在上述国家,新生儿预期寿命较短，某些区域生活质量极低。

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