In recent years, Delhi reduced pollution after rickshaws which had used high-polluting two-stroke engines switched to using cleaner-burning liquefied natural gas, he said.

他说，最近几年德里通过把黄包车高污染的两冲程马达改装成使用更清洁的液化天然气从而减少了污染物的排放。

youdao

In Scotland, the number of wild salmon have been reduced because of uncontrolled deep-sea and coastal netting, by pollution, and by various other threats to the fish's habitat.

在苏格兰，野生鲑鱼的数量已经减少，这是由于不受控制的深海和沿海捕捞、污染，以及对鲑鱼栖息地的各种其他威胁。

youdao

Fuel consumption and pollution might be reduced by smoothing traffic flow and running vehicles close enough to each other to benefit from aerodynamic drafting.

车流通畅，相互紧随行驶的车辆能利用前车产生的较小的空气阻力，这些都可能减少油耗和污染。

youdao

It ordered one-third of the city's 3 million cars off the streets, which significantly reduced pollution.

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While a state-of-the art system installed in Chile has reduced pollution in the city of Santiago, a bungled adjustment has also left millions of passengers reeling and hundreds of others suing the government.

NPR: In Chile, Commuters Sue City over Transit System

In the long run, though, it seems the train has reduced the pollution formerly caused by cars and trucks and reduced the number of animals killed by vehicles driving through the park.

BBC: Eco-scorecard to the world��s great attractions