The coal it produces is mostly poor in quality and rich in ash; it should be washed before shipping to make it more efficient, but is not.

它所产的煤炭大部分质量差而灰尘多；要想提高这些煤炭的效率，在装运之前应该要清洗但它们并没有被清洗过。

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They also tend to produce poor-quality coal which generates relatively high levels of pollution when burned.

他们也倾向于生产劣质煤，这些煤在燃烧时产生相对高的污染水平。

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Born into a poor working-class family in Donetsk, a coal-mining centre, he lost his parents early.

生于煤矿中心顿涅茨克的一个贫穷工薪阶层家庭，幼年时期父母双亡。

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The World Bank should support poor countries that need coal-powered energy in spite of its contribution to climate change, its president has said.

BBC: Jim Yong Kim

They were still a new denomination then, but had spread rapidly in the last fifty years around a nation of exploited factory workers, coal miners, and rural and inner-city poor.

NPR: Excerpt: 'The Prince of Frogtown'

Duke operates in the resource-poor Carolinas and built some of the world's biggest coal plants in the 1960s and 1970s, when people were more concerned about cheap, secure energy supplies than co2 levels.

FORBES: Magazine Article