US patents for clean energy technologies in 2009 were at an all-time high, at 1,125.

2009年，美国清洁能源技术专利数达到1125件，创历史新高。

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Those areas are thought to include energy efficiency, "clean coal" technologies and electric cars.

人们认为这些领域包括能源效率、“净煤”技术和电动汽车。

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Those areas are thought to include energy efficiency, "clean coal" technologies and electric cars.

人们认为这些领域包括能源效率、“净煤”技术和电动汽车。

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