VOA慢速英语:Next Step After Carbon: Knowing Your Nitrogen Footprint

短语讲解：

1. A carbon footprint is the amount of carbon dioxide pollution that we produce as a result of our activities.

as a result of 由于…的结果
例句：He was injured as a result of boiler explosion.
他因锅炉爆炸而受伤。

2. Some people try to reduce their carbon footprint because they are concerned about climate change.

be concerned about 关心，担心
例句：Everybody is concerned about the future of his country. 
 每个人都关心自己国家的前途。
climate change 气候变化

3. It contributes to smog, acid rain, loss of biodiversity, dead zones along the coast, global warming, stratospheric ozone depletion.

contribute to 促成，导致
例句：A number of factors contribute to this. 
对于此总可以归诸于许多因素。
global warming 全球变暖

4. Professor Galloway says animal protein plays a big part.

play a part 扮演某角色，起作用
例句：Under certain circumstances their country of origin may also play a part. 
 在某些情况下，他们的本籍也可能起一定的作用。

5. He points to the example of cattle that are given feed grown with nitrogen fertilizer.

point to 表明，指出
例句：Critics point to the continuing instability of the company. 
 评论家们强调公司的形势继续不稳。