名校最新大学英语四级阅读精讲的系列讲义：(133)_大学英语阅读

名校最新大学英语四级阅读精讲的系列讲义：(133)

　　C)They broke down and the carbon content was mainly absorbed in the soil.

　　D)They absorbed more carbon dioxide.

　　4.Scientist Ram Oren is of the opinion that common beliefs of the trees ability to absorb carbon dioxide are____.

　　A) biased B) insightful

　　C) overoptimistic D) totally wrong

　　5.The word it probably refers to ____.

　　A) carbon dioxide B) nitrogen

　　C) atmosphere D) coal

　　答案与解析：

　　1.A。本文主要介绍了一些科学家提出的关于树林与二氧化碳关系的新学说。主题题。B),D)均与本文无关;C)则由于实验显示树木吸收并不那么有效，因此从本文观点来看正好错误。

　　2.D。研究者把树木放入过量二氧化碳的环境中研究树木相应的生长规律。细节推理题。关键语句： The trees grew thirty-four percent faster during the first three years. However, in time, the trees slowed to about their normal growth rate. The scientists say this is because trees need other nutrients, such as nitrogen. 可以看出是研究生长规律.A),B),C)均和本文无关。

　　3.B。在第二个试验中落下的树叶分解后,包含的主要碳成分转化为二氧化碳。客观事实题。关键语句： They discovered that as the leaves broke down into the soil, all the carbon was not trapped in the soil. Much of it was released into the atmosphere as carbon dioxide. 而A), C), D) 均错误。