北京城区施行单双号交通管制削减了从汽车和卡车生产的50％的废气排放量。

The traffic bans within the city have virtually cut the amount of emissions produced from cars and trucks by 50%.

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他说：“它的废气排放量是零，不排放碳，而且氢是宇宙中含量最丰富的物质。”

It is zero emissions, there is no carbon, he said. And hydrogen is the most plentiful element in the universe.

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他说：“它的废气排放量是零，不排放碳，而且氢是宇宙中含量最丰富的物质。”

"It is zero emissions, there is no carbon," he said. "And hydrogen is the most plentiful element in the universe."

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Clearly, if I did nothing more, but I took every car, doubled its fuel economy, its emissions would go to 50% of what they are now, no other changes being made.

显然，如果我什么也不做，但是我把没量车的汽油价加倍，汽车废气排放量就会是现在的一半了，别的不会有什么改变。

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