People saw a need for free transportation, and they wanted to help control pollution.

人们看到了免费交通的必要性，他们想帮忙控制污染。

youdao

WHO said the reasons for the high pollution levels varied, but that often rapid industrialization and the use of poor quality fuels for transportation and electricity generation are to blame.

世界卫生组织说，导致高污染水平的原因各有不同，不过通常是由迅速工业化及在交通和发电上使用低质量的燃料导致的。

youdao

When something has to come from far away, obviously there is transportation, be this plane, train, truck, or ship, transportation involves pollution.

商品从远方运过来，自然需要用飞机、火车、卡车、轮船等来运输，而这些运输就涉及到污染。

youdao

And the dymaxion car -- which could have provided safe, pollution-free transportation using little gasoline -- was never produced.

VOA: special.2010.05.30

But pollution is not the only environmental concern with transportation.

VOA: special.2010.01.11

Most of the data comes from the industrialized world. Not surprisingly, burning fossil fuels for transportation and electrical generation top the list for their contributions to climate change, acid rain and toxic pollution.

VOA: standard.2010.06.04

They could be employed in more creative ways for journalistic investigations into land use, or industrial pollution, or transportation.

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Mr. HINCHMAN: We've chosen the stricter California program because it's the only policy option available to us that we can use to reduce pollution emissions from the transportation sector, which is the most polluting and fastest-growing problem in terms of air quality in the Northeast.

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In the Environmental Protection Agency this clearly lies in your area of responsibility, yet if it is about pollution created by airplanes, the Department of Transportation shares oversight.

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