1、课时作业14Using languageAEvery spring flowers suddenly come out everywhere on the same day, as if they had an agreement with one another. But how exactly do plants “know” when to flower?Its a question puzzling biologists for years. But according to Science Daily, a US research group may have finally ans
2、wered itthe secret lies in a protein called FKF1.This allows plants to sense the differences in day lengths so that they can tell the seasons are changing.Researchers found the protein when they were studying a plant called Arabidopsis. They found its a photoreceptor (感光器). This means its sensitive
3、to, and can be activated (激活) by sunlight.Plants produce the protein every day in the late afternoon throughout the year. If theres no light at this time, for example, in winter when the sun goes down early, it may not be activated. But when spring comes and the days get longer, it can be activated
4、by daylight and the plants “know” its time to flower.Although researchers have only studied how the FKF1 protein works in the Arabidopsis, they believe that the process is similar in many other more complex (复杂) plants, including crops like rice and wheat. This could be useful to the agricultural in
5、dustry.“If we can control the timing of flowering, we might be able to produce more crops by putting it forward or putting it off，” a leader of the study said. “Also, if we could control the timing of flowering in horticultural (园艺的) plants, they may be worth more money.”What an amazing thing to thi
6、nk about this!本文是一篇说明文。文章介绍了研究人员发现一种叫FKF1的蛋白质告诉植物开花的时间。1How do plants know when to flower?AThey get messages from some insects.BThey receive messages from other plants.CA certain protein tells them the time to flower.DSunlight produces a protein in them to help them flower.答案：C解析：细节理解题。根据第二段中的“But a
7、ccording to Science Daily, a US research group may have finally answered itthe secret lies in a protein called FKF1.”可知，一种叫FKF1的蛋白质告诉植物开花的时间，故C项正确。2What can we learn from the article?AThe study may benefit agricultural industry.BWe may have plants that flower all year round.CPlants dont flower in co
8、ld weather and short days.DResearchers found the protein by studying rice and wheat.答案：A解析：细节理解题。根据倒数第三段中的“This could be useful to the agricultural industry.”可知，这项研究可能对农业有益，故A项正确。3Whats the writers attitude towards the study?ANegative. BPositive.CUncaring. DUnclear.答案：B解析：推理判断题。倒数第二段说如果我们能控制开花的时间，我们
9、或许可以通过提前或推迟开花来生产更多的作物。此外，如果我们能控制园艺植物开花的时间，它们可能更值钱，最后一段作者认为这是一件不可思议的事情，由此可知作者对这项研究持积极的态度，故B项正确。BBreathing dirty air comes at a high price. Air pollution lowers the average life spans (寿命) by a year worldwide and in more polluted parts of Asia and Africa, dirty air shortens lives up to twice that much
10、. Scientists shared their new findings in Environmental Science & Technology Letters. The study used data gathered in 2016 as part of a project known as the Global Burden of Disease and was the first major countrybycountry look at the connection between the length of life and whats known as fine PM.
11、Air pollution has been linked to many health problems. Most earlier studies had looked at how tiny air pollutants affected rates of illness or death. Joshua Apte is an environmental scientist at the University of Texas at Austin. By looking at life expectancy (预期寿命), his team had hoped to make the t
12、hreat easier to understand. PM2.5 is what scientists call tiny particles (颗粒) of pollution in the air. Higher levels of PM2.5 can cause health problems and cut months, if not years, from the average length of life. This analysis shows how pollution affects life expectancy in different parts of the w
13、orld.The World Health Organization (WHO) recommends limiting PM2.5 to 10 micrograms per cubic meter of air. Aptes group calculated how holding pollution to this low level would help people. In countries with very dirty air, meeting this standard would lengthen peoples lives. However, in countries wh
14、ose air already meets this standard, the study shows no gain in life expectancy. In other words, meeting the WHO standard wont reduce health costs resulting from dirty air because even below 10 micrograms per cubic meter, pollution still causes serious risks. Meanwhile, the scientists compared how o
15、ther threats including smoking and cancer shorten the length of life across the globe.本文是一篇说明文。在全球范围内，空气污染使人的平均寿命降低了一年，而在污染更严重的亚洲和非洲地区，空气污染使人的寿命缩短了两倍之多。科学家们在环境科学与技术快报上分享了他们的新发现。该研究分析了不同国家居民的寿命与PM之间的关系。4What is special about the study?AIt won recognition from a professional journal.BIt discussed heal
16、th problems caused by air pollution.CIt gathered lots of data for the Global Burden of Disease.DIt analyzed the link between life spans and PM by country.答案：D解析：细节理解题。根据第一段中The study used data gathered in 2016 as part of a project known as the Global Burden of Disease and was the first major country
17、bycountry look at the connection between the length of life and whats known as fine PM.(该研究使用了2016年一个名为“全球疾病负担” (Global Burden of Disease)项目的一部分收集的数据，这是首次对寿命长短与“细颗粒物” (fine PM)之间关系进行逐个国家研究。)可知，研究的特殊之处是该研究分析了不同国家居民的寿命与PM之间的关系。故选D。5What is Joshua Aptes team trying to do?AHelp people better understand
18、air pollution.BStudy life expectancy in different countries.CKnow how small air pollutants affect health.DDeal with different kinds of health problems.答案：A解析：细节理解题。根据第二段中Joshua Apte is an environmental scientist at the University of Texas at Austin. By looking at life expectancy (预期寿命), his team had
19、 hoped to make the threat easier to understand.(约书亚阿普特 (Joshua Apte)是德克萨斯大学奥斯汀分校的环境科学家。通过观察预期寿命，他的团队希望能让这种威胁更容易理解。)可知，Joshua Apte的团队帮助人们更好地了解空气污染。故选A。6What will happen if a country limits PM2.5 to 10 micrograms per cubic meter of air?APeoples life spans will surely increase.BIt will get strong suppo
20、rt from the WHO.CPeoples health may not be much improved.DIt will guarantee people clean air.答案：C解析：推理判断题。根据最后一段中The World Health Organization (WHO) recommends limiting PM2.5 to 10 micrograms per cubic meter of air.(世界卫生组织 (WHO)建议将PM2.5浓度限制在每立方米10微克以内。)和In other words, meeting the WHO standard wont
21、reduce health costs resulting from dirty air because even below 10 micrograms per cubic meter, pollution still causes serious risks.(换句话说，达到世界卫生组织的标准并不能降低空气污染造成的健康成本，因为即使低于每立方米10微克，污染仍然会造成严重的风险。)可知，如果一个国家将PM2.5浓度限制在每立方米10微克，人们的健康状况可能不会有太大改善。故选C。7What might be discussed in the following paragraphs?AH
22、ow cleaning up the air can lengthen lives.BHow air pollution shortens lives by country.CHow other threats shorten life expectancy.DHow all the countries deal with severe pollution.答案：C解析：推理判断题。根据最后一段中Meanwhile, the scientists compared how other threats including smoking and cancer shorten the length
23、 of life across the globe.(与此同时，科学家们比较了包括吸烟和癌症在内的其他威胁是如何缩短全球寿命的。)由此推知，接下来要讨论的是“其他威胁如何缩短预期寿命”。故选C。Have you ever been bored and decided to check social media, only to find out that your best friend is at Disneyland, that one of your classmates is eating delicious pizza at your favorite pizza store, an
24、d that one of your soccer teammates is climbing the Eiffel Tower in Paris? Have you ever had that feeling that others are experiencing things and enjoying life more than you are? Oh, man! Youre missing out! _1_ Researchers call that feeling the fear of missing out or FOMO._2_ Its so easy today to se
25、e what your friends are doing from the social media. Unluckily, we only have so much time in the day and only so much money to spend on food or entertainment. It would be impossible for us to enjoy all the same activities we see others take part in on social media.Rather than realizing this basic tr
26、uth, though, we usually let FOMO lead us to compare our lives with those of others on social media. _3_ Why? We know all the sides of our livesboth good and bad. But all we see on social media are the pictureperfect moments others share. _4_ FOMO makes us check social media more frequently, leading
27、to addiction and a negative cycle that can be hard to break. Researchers have found that social media and FOMO can cause serious negative results, including feeling of depression, loneliness and boredom._5_ Researchers advise that we stop looking to social media for happiness. Instead, we should foc
28、us our attention on our real lives, including the people around us and all the things were grateful for.AHave you ever experienced FOMO?BAt least thats what you might think.CThis certainly leaves us feeling dissatisfied.DSo how do we break the cycle and avoid FOMO?EOver 75% of young people report fe
29、eling FOMO from time to time.FAs famous Theodore Roosevelt said, “Comparison is the thief of joy.”GIf you let FOMO control you, the only thing youll really be missing out on is your own life.本文是一篇说明文。文章讲述了社交媒体对人们的影响，呼吁人们关注周围真实的世界。1B解析：根据上文“Have you ever had that feeling that others are experiencing
30、things and enjoying life more than you are? Oh, man! Youre missing out！”可知此处讲述人们自己的感受。故B项“At least thats what you might think.”(至少你可能会这么想)很好地承接上文。故选B项。2E解析：结合上文“Researchers call that feeling the fear of missing out or FOMO.”及下文“Its so easy today to see what your friends are doing from the social med
31、ia.”可知，此句需承上启下，E项“超过75%的年轻人报告说他们时不时会有情绪低落的感觉。”承接上文“missing out or FOMO”，引出下文对于这种感觉的说明。故选E项。3C解析：根据上文“Rather than realizing this basic truth, though, we usually let FOMO lead us to compare our lives with those of others on social media.”可知人们通常与其他人进行比较；再根据下文“We know all the sides of our livesboth good
32、 and bad. But all we see on social media are the pictureperfect moments others share.”可知我们只是知道他们的美好瞬间。C项“This certainly leaves us feeling dissatisfied.”(这会使我们不高兴)承上启下，符合语境。故选C项。4F解析：根据下文“FOMO makes us check social media more frequently, leading to addiction and a negative cycle that can be hard to b
33、reak.”可知比较会使我们产生消极情绪；上文主要讲述攀比使人不舒服。F项中“Comparison is the thief of joy”很好地承上启下。故选F项。5D解析：根据下文“Researchers advise that we stop looking to social media for happiness.”可知研究人员给出了解决办法；D项“So how do we break the cycle and avoid FOMO？”给出如何解决的疑问。故选D项。阅读下面材料，根据其内容和所给段落开头语续写两段，使之构成一篇完整的短文。续写的词数应为150左右。Craig wat
34、ched his old sister, Riley, and her friend Liz race up and down the lake on their skates, avoiding other hockey (曲棍球) players. Their skate blades looked like silver smoke. When the game was over, the girls skated up to the bench where Craig was sitting. Craig asked Riley what skating felt like.“When
35、 I go really fast, I feel like Im flying，” she said.Thats silly, thought Craig. Flying is something birds do in the air, not something people do on ice skates.Then he watched Riley go back out on the ice. She skated around and around the edge of the lake with her arms pumping and her scarf trailing
36、behind her. Soon she went so fast that her arms looked like wings and her scarf looked like a feathery tail. Maybe skating really was like flying.When Riley sat down to take her skates off, Craig said, “I wish I could fly.”Riley retied her skate laces and crouched next to Craig. “Get on my back，” sh
37、e said, and Craig did. Riley started skating, but Craig didnt feel like he was flying. It just felt like a shaking piggyback ride. “Youre too heavy，” Riley said. “I cant go fast when Im carrying you.” She skated slowly back to the bench. Craig got off her back. “Even if you could go fast, I wouldnt
38、be flying，” he said sadly. “I need skates to fly.”Riley didnt say anything on the walk home, but a few days later she asked Craig if he wanted to go skating.“To watch？” he asked. “No, to skate，” she said cheerfully. “Mom and I found a pair of my old skates. They might fit you.” The skates were a lit
39、tle big, but when Riley stuffed newspaper in the toes, they fit. Craig couldnt stop smiling. He didnt want to take them off, but he had to so he could walk to the lake. Riley and Liz went with him. They carried their hockey sticks and a wooden chair. Hardly had they got to the lake when Craig put hi
40、s skates back on and Riley helped him onto the ice.答案Paragraph 1: Then she put his hands on the back of the chair. “Hang on this and you wont fall，” she said. His feet trembling, Craig tried to move cautiously with his hands grabbing the chair firmly. Riley and Liz cheered him on as he started to mo
41、ve forward. But Craig slowly lowered his head, frowning, as he inched along and he even couldnt skate without the chair. This wasnt like flying at all. Realizing his frustration, Riley patted his shoulder and comforted, “It takes practice. Someday you will.” Then she winked at Liz and whispered some
42、thing to her. Paragraph 2: After a while, each girl took one of Craigs hands. “Someday youll fly on your own，” Riley said. “But today Liz and I will help you.” They started skating, pulling Craig with them. The girls went faster and faster, and so did he. Craig felt the wind touching his face merrily with brilliant sparkle in his eyes. When he looked down, his skate blades looked like a silver light. “Im flying！” he yelled, and the words blew away in the wind like a birds happy song.