In addition, two different groups of scientistsannounced on March 28 that they had found signs of methane (甲烷) in the Martian atmosphere (大气)．The gas is a waste product of living creatures and could be produced by microbes (微生物) living in the red planet's soil.

　　But scientists such as Dr Lisa Pratt, a biologist at Indiana University, say that these microbes will be put in danger by the little earth project.“Before we have even discovered if there is life on Mars, we are talking about carrying out projects that would destroy all these native life forms, all the strange microbes that we hope to find buried in the soil，” said Dr Pratt.This view is shared by Monica Grady, a planetary scientist at the Natural History Museum, London.“We cannot risk starting a global experiment that would wipe out the precious information we are looking for.” she said, “This is just wrong.”

　　20．The passage is about________.

　　A．a plan turning Mars into a little earth

　　B．the necessity of changing Mars

　　C．Mars supporting life

　　D．finding water in the Mars

　　21．We can infer from the passage that________.

　　A．water is a crucial factor for life

　　B．the project will have little effect on the native life forms supposed to live on the Mars

　　C．Monica Grady is in favour of carrying out the little earth project

【2017届高考英语一轮复习课时作业23：Unit 3《Life in the future》（新人教版必修5陕西专用）】相关文章：

★ 四川省2016届高考英语一轮复习课时作业（28） Module 4 Carnival 外研版必修5

★ 【浙江专用】2014届高考英语一轮复习课时作业(十一)必修3Unit 1《Festivals around the world》

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

★ 2017届高考英语二轮复习大题冲关秘籍语法填空：解题技巧（含解析）

★ 【新人教版 必修2】2016届高三英语一轮总复习（佳作诵读+考点锁定+高频考点+课堂双基+课时作业）精品课件《unit 4 Wildlife protection》（115张ppt）

★ 四川省2016届高考英语一轮复习课时作业（46） Module 4 Which English 外研版选修8

★ 2014届高考英语一轮复习课时作业(三十二)选修6Module 2《Fantasy Literature》（外研版）

★ 【北京专用】2014届高考英语一轮复习方案课时作业：必修4 Unit 3 A taste of English humour

★ 2017届江苏省淮安市新马中学高考牛津译林版英语一轮复习活动单：模块7 unit 4《Public transport》

★ 【浙江专用】2014届高考英语一轮复习课时作业(三十一)选修7Unit 1《Living well》