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来源:雅诚德英语网
Since the beginning of the 19th century, America has had trouble with environmental problems, air pollution in particular.
自19世纪初以来,美国一直面临着环境问题的困扰,特别是空气污染。
Since the beginning of the 19th century, America has had trouble with environmental problems, air pollution in particular.
自19世纪初以来,美国一直面临着环境问题的困扰,特别是空气污染。