Even if scientists did discover another reasonable explanation for the warming recorded so far, that would give birth to a difficult question. As Robert Henson puts it: “If some newly discovered factor is to blame for the climate change, then why aren't carbon dioxide and the other greenhouse gases producing the warming that basic physics tells us they should be？”

　　The only way to prove with 100% certainty that humans are responsible for global warming would be to run an experiment with two identical Earths—one with human influence and one without. That obviously isn't possible, and so most scientists are careful not to state human influence as an absolute certainty.

　　文章大意：全球变暖是不是人类活动的原因？本文进行了探讨。

　　5．In most scientists' opinion, the global warming is mainly caused by________.

　　A. solar activity

　　B. volcanic activity

　　C. natural factors

　　D. human factors

　　答案：D　细节理解题。由第一段可知，全球变暖是由人类活动这一因素引起的。

　　6．The text is developed by________.

　　A. giving typical examples

　　B. following the order of space

　　C. analyzing a theory and arguing it

　　D. comparing and finding differences

　　答案：C　推理判断题。由全文可知，本文先提出了一个理论，然后进行了反驳。

【2014届高考英语一轮 Unit5 《The power of nature》课后强化作业 新人教版选修6】相关文章：

★ 北京市2014高考英语一轮复习 练习手册（34）选修7 Unit 4 Sharing（含解析）新人教版

★ 【人教版】2014届高考英语一轮复习指导考点针对练：必修2 unit2《The Olympic Games》

★ 2014届高考英语一轮复习课时作业(四十三)选修8Module 1《Deep South》（外研版）

★ 2014届高考英语一轮复习课时作业(三十九)选修7Module 3《Literature》（外研版）

★ 四川省2016届高考英语一轮复习课时作业（44） Module 2 The Renaissance 外研版选修8

★ 【北京专用】2014届高考英语一轮复习方案课时作业：必修2 Unit 5 Music

★ 【人教版】2014届高考英语一轮复习指导考点针对练：必修1 unit3《Travel journal》

★ 2014届高考英语一轮复习选修7参考答案（外研版）

★ 2014届高考英语一轮复习选修6参考答案（外研版）

★ 【人教版】2014届高考英语一轮复习指导考点针对练：必修4 unit1《Women of achievement》