求翻译：随着世界人口越来越密集，空气污染已经成了严重的问题。空气污染主要来源于四个主要的人类活动领域：工业 能源业 交通运输业 以及农业。经营工厂，为火车 飞机 和公共汽车提供动力都需要能源。几乎所有这些能源都是通过燃烧产生的，这就会造成空气污染。科学家正在研究能减少环境破坏的新发电方式。公共环境意识的增强促成了诸如回收利用等活动的产生。是什么意思？

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As the world population density, air pollution has become a serious problem. The main sources of air pollution in four main areas of human activity: industrial energy industry transportation and agriculture. To operate factories in the train and bus powered aircraft all require energy. Almost all of

Is more and more crowded along with the world population, the air pollution had already become the serious issue.Air pollution main origin in four main humanity field of activity: Industry energy industry transportation shipping industry as well as agriculture.Manages the factory, provides the power

As the world population more and more crowded, air pollution has become a serious problem. Air pollution comes mainly from four main fields of human activity: industrial energy, transportation and agriculture. Operates a factory, power planes for trains and buses all need energy. Almost all of this

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