1·Nitrogen dioxide is a pollutant emitted by automobiles.
二氧化氮是汽车排放的一种污染物。
2·Our air quality now suffers from the effects of pollutants emitted directly from our cars.
我们的空气质量现在受到了汽车直接排放的污染物的影响。
3·Therefore, the methane now emitted from open landfills should instead be burned to produce electricity.
因此，现在从露天垃圾填埋场排放的甲烷应该被用来发电。
4·That’s the same amount of carbon dioxide that would be emitted if a car could drive to the moon and back 188 times (90 million miles).
这个数量等于如果有一辆汽车可以开到月球（90万英里），那么来来回回开188次所排放的二氧化碳数量。
5·They compared these to data already available on the cattle and pigs' growth rate and the rates at which they emitted the same pollutants.
他们将获得的数据同牛和猪在生长率及在排放等量污染物情况下生长率方面的数据做了比较。