2020-2021学年英语新教材外研版选择性必修第一册课时作业（十七） WORD版含解析.doc

1、课时作业(十七)Unit 6Section Discovering Useful Structures.阅读理解ABlood Falls are at the tip of a giant glacier in Antarctica. As its name suggests, the icy face of Blood Falls is redbut not from blood. Instead, the water gets its color because its rich in iron. When the water comes out from its underground

2、beginnings, the iron is exposed to the air and quickly forms the red rust.A scientist recently studied the rusty water and came up with some surprising results. The water that feeds Blood Falls probably comes from a salty underground lake. Its home to microbes that surprisingly dont need oxygen to s

3、urvive.“This salty lake is a sort of time capsule，” said Jill Mikucki, who led the study. When she and her team studied the water, they found no oxygen but lots of iron. They suspected that the underwater lake formed when a giant glacier, now 1,300 feet thick, moved over the salty lake at least 1.5

4、million years ago. This trapped the water and everything in it in an oxygenfree environment.Unlike human beings and most other forms of life, the microbes from Blood Falls dont need oxygen to live. Instead, they are able to exist using the iron.The study gives us more information about our own plane

5、t. It may be useful in other scientific areaslike the search for life on other planets. If scientists find living things on the Earth that live on iron instead of oxygen, researchers might have a better idea of where to look for life elsewhere.1For what do Blood Falls get the name?AThey are rich in

6、oxygen.BThey reflect their red surroundings.CTheir water rich in iron is red.DThey are composed of blood.2What probably made Jill Mikucki most surprised?AThe discovery of a salty underground lake.BMicrobes that dont need oxygen to survive.CThe movement of a giant glacier.DThe color of Blood Falls.3W

7、hy did Jill Mikucki believe this salty lake is a sort of time capsule?ABecause it was formed by a giant glacier.BBecause it could be used to study life on other planets.CBecause it was home to special microbes.DBecause it was formed more than 1.5 million years ago.4What do the microbes from Blood Fa

8、lls live on?AAir. BWater.CIron. DOxygen.B“You can use me as a last resort (选择), and if nobody else volunteers, then I will do it.” This was an actual reply from a parent after I put out a request for volunteers for my kids lacrosse (长曲棍球) club.I guess that theres probably some demanding work schedul

9、e, or social anxiety around stepping up to help for an unknown sport. She may just need a little persuading. So I try again and tug_at_the_heartstrings. I mention the single parent with four kids running the show and I talk about the dad coaching a team that his kids arent even on.At this point the

10、unwilling parent speaks up, “Alright. Yes, Ill do it.”Im secretly relieved because I know theres real power in sharing volunteer responsibilities among many. The unwilling parent organizes the meal schedule, sends out emails, and collects money for endofseason gifts. Somewhere along the way, the sam

11、e parent ends up becoming an invaluable member of the team. The coach is able to focus on the kids while the other parents are relieved to be off the hook for another season. Handing out sliced oranges to bloodthirsty kids can be as exciting as watching your own kid score a goal.Still, most of us vo

12、lunteers breathe a sigh of relief when the season comes to a close. That relief is coupled with a deep understanding of why the same people keep coming back for more：Connecting to the community (社区) as you freely give your time, money, skills, or services provides a real joy. Volunteering just feels

13、 so good.In that sense, Im pretty sure volunteering is more of a selfish act than Id freely like to admit. However, if others benefit in the process, and I get some reward too, does it really matter where my motivation lies?5What can we infer about the parent from her reply in paragraph 1?AShe knows

14、 little about the club.BShe isnt good at sports.CShe just doesnt want to volunteer.DShes unable to meet her schedule.6What does the underlined phrase “tug at the heartstrings” in paragraph 2 mean?AEncourage teamwork.BAppeal to feelings.CPromote good deeds.DProvide advice.7What can we learn about the

15、 parent from paragraph 3?AShe gets interested in lacrosse.BShe is proud of her kids.CShell work for another season.DShe becomes a good helper.8Why does the author like doing volunteer work?AIt gives her a sense of duty.BIt makes her very happy.CIt enables her to work hard.DIt brings her material rew

16、ards.七选五Sleeping in class prevents you from paying attention to the teacher as well as stops you from learning about the material that is being taught. _1_ It is important to determine why you are falling asleep in class and try to change the situation so that you are able to stay awake and pass all

17、 of your classes. There are a number of different tricks you can use to try to stay awake.Get a full nights sleep on school nights. It is reported that teenagers may need more sleep than adults. _2_ This is a key part to staying awake in class. If you are not tired, you are unlikely to fall asleep.E

18、at a healthy breakfast full of nutritious food. _3_ If you get hungry or tired in the middle of the day, try eating a healthy snack like a piece of fruit or some biscuits._4_ If you are actively engaged in the information the teacher is presenting, you are less likely to doze off. Taking notes, aski

19、ng questions and otherwise getting involved in classroom activities and discussions will make you far less likely to doze off.Contact your doctor in order to rule out medical conditions that can cause you to fall asleep. _5_ Prescription drugs may also cause sleepiness as a side effect, so discuss a

20、ny medicine you are taking with your doctor.AGet involved during class.BEarly to bed, early to rise.CSleeping more helps a lot in your study.DIt can also get you in trouble with your teachers.EIt can provide you with enough protein to fuel your body.FGo to bed earlier and make sure you get as many h

21、ours of sleep as your body needs.GIf you have a medical condition that is causing you to fall asleep in class, it will need to be treated by a professional.课时作业(十七).阅读理解A【语篇解读】本文是一篇说明文。科学家在南极洲发现了神奇的、富含铁元素的“血瀑布”，此次发现提供给我们许多有关地球的信息，这对地球生命的研究也许具有划时代的意义。1答案与解析：C推理判断题。由第一段中的Instead, the water gets its co

22、lor because its rich in iron. When the water comes out from its underground beginnings, the iron is exposed to the air and quickly forms the red rust.可以判断，“血瀑布”之所以有此名是因为水里富含铁元素，而铁暴露在空气中，很快就会形成红色的铁锈。2答案与解析：B细节理解题。由第二段中的.surprisingly dont need oxygen to survive.并结合第三段可知，这些微生物不需要氧气就能生存，这一点令她感到惊奇。3答案与解析

23、：D推理判断题。由第三段中的They suspected that the underwater lake formed when a giant glacier, now 1,300 feet thick, moved over the salty lake at least 1.5 million years ago.可以得出正确选项。4答案与解析：C细节理解题。由第四段中的Instead, they are able to exist using the iron.可知这些微生物依靠铁元素生存。B【语篇解读】本文是一篇记叙文。主题语境为人与社会，主题语境内容为志愿服务。文章记述了作者请一

24、位家长做志愿者的故事。文章侧重社会服务和人际沟通素养的培养。5答案与解析：C推理判断题。本题题干意为：从第一段那位家长的回答中我们可以推断出关于她的什么？文章中，那位家长的回答是“你可以把我作为最后一个选择，如果没有其他人愿意当志愿者，那么我就做”。根据其回答可以知道，她其实是不太愿意做志愿者的，故C项正确。6答案与解析：B词义猜测题。本题题干意为：第二段中的画线短语“tug at the heartstrings”的意思是什么？根据上下文可知，此处表示“我”又试了一次，这回开始打感情牌。画线短语意为“触动心弦”，故B项正确。A：鼓励团队合作；C：促进良好行为；D：提供建议。7答案与解析：D推

25、理判断题。本题题干意为：从第三段中，我们能够得知那位家长的什么情况？在文章的第三段，作者记述了那位家长在活动中所做的事情，即安排饮食计划、发送邮件、募集资金等，她成了团队中一个重要的成员。因此D项(她成了一个好助手)正确。8答案与解析：B推理判断题。本题题干意为：为什么作者喜欢做志愿工作？根据文章倒数第二段中的“Connecting to the community.provides a real joy”以及“Volunteering just feels so good.”可知，作者认为，做志愿工作能让她开心。故B项正确。A：这给予她一种责任感；C：这让她能努力工作；D：这给她带来了物质上

26、的回报。.七选五【语篇解读】本文为指导类说明文。课堂上睡觉会妨碍你听讲。弄清楚你课上睡觉的原因并改变这种状况对你的学习非常重要。文章就“如何应对上课睡觉以保持头脑清醒”提供了几种有效的方法。1答案与解析：D本空前一句介绍了上课睡觉的害处。根据D选项中的also可以判断，此选项也在讲上课睡觉的影响，故D选项符合前后逻辑，内容上也相关，故选D。2答案与解析：F该空所在段落主题句为第一句话，即“上学时的晚上要得到充足的睡眠”，故F项与本段主题相符。3答案与解析：E由本段主题Eat a healthy breakfast full of nutritious food.可以判断，该空所表达意思与饮食营养有关，故选E项。4答案与解析：A根据文章特点可以判断此空为祈使句，并且是本段主题句。再根据本段内容可以判断应选A，即“积极参与课堂”。5答案与解析：G根据本段语境为药物导致睡眠可以判断G项为最佳选项。