英语必修 第三册Unit 4 Space Exploration单元测试课后练习题

这是一份英语必修 第三册Unit 4 Space Exploration单元测试课后练习题，共16页。
阅读下列短文, 从每题所给的A、B、C、D四个选项中, 选出最佳选项。
A
Astrnmy is the ldest science knwn t man. Thusands f years ag, man lked at the stars and wndered abut the heavens. But man was limited by what he culd see with his eyes alne.
The Greeks studied astrnmy ver 2，000 years ag. They culd see the size，clur and brightness f a star. They culd see its place in the sky. They watched the stars mve as the seasns changed. But the Greeks had n tls t help themselves study the heavens.
Each new tl added t the field f astrnmy helped man reach ut int space. Until there were telescpes，men did nt knw much abut the mn. They did nt knw that the planet called Saturn (土星）had rings arund it. Their sight was s limited that they culd nt see all the planets. In the early 1700s，peple thught there were nly six planets. Neptune (海王星)，the last f eight planets t be discvered, was nt seen until 1846.
Befre the spectrscpe (分光镜），man did nt knw what kind f gases was in the sun r ther stars. Withut the radi telescpe，we didn’t knw that radi nises came frm far ut in space.
Tday, astrnmy is a grwing science. We had learned mre in the last fifty years than in the whle histry f astrnmy.
1. When the Greeks watched the stars, they culd____________.
A. knw what the stars were made f
B. nt see their places in the sky
C. help themselves study the heavens
D. watch the stars mve as the seasns changed
2. Until there were ____________，man knew very little abut the mn.
A. telescpes
B. spectrscpes
C. radi telescpes
D. spaceships
3. Which f the fllwing sentences is NOT true?
A. Astrnmy is the ldest science that humans have knwn.
B. Astrnmy is develping fast with the help f technlgy.
C. In the early 1700s, peple didn’t knw the existence f Neptune.
D. Over 2,000 years ag，the Greeks knew the planet Saturn had rings arund it.
B
Edmund Hailey was an English scientist wh lived ver 200 years ag. He studied the bservatins f cmets(彗星）which ther scientists had made. The rbit (轨道）f ne particular cmet was a very difficult mathematical prblem. He culd nt figure it ut. Neither culd ther scientists wh dealt with such prblems.
Hwever，Hailey had a friend named Isaac Newtn, wh was a brilliant mathematician. Newtn thught he had already wrked ut that prblem, but he culd nt find the papers n which he had dne it. He tld Hailey that the rbit f a cmet had the shape f an ellipse(椭圆形）.
Then Hailey set t wrk. He figured ut the rbits f sme f the cmets that had been bserved by scientists. He made a surprising discvery. The cmets that had appeared in the years 1531，1607, and 1682 all had the same rbit. Yet their appearance had been 74 t 79 years apart.
This seemed very strange t Hailey. Three different cmets fllwed the same rbit. The mre Hailey thught abut it，the mre he thught that there had nt been three different cmets as peple thught. He cncluded that they had simply seen the same cmet three times. The cmet had gne away and had cme back again.
It was an astnishing idea! Hailey felt certain thugh (然 而)t make a predictin (预言)f what wuld happen in the future. He decided that this wuld appear in the year 1758. There were 53 years t g befre Hailey’s predictin culd be tested- In 1758 the cmet appeared in the sky. Hailey did nt see it, fr he had died sme years befre. Ever since then that cmet has been called Hailey’s cmet, in his hnur.
4. Edmund Hailey figured ut the rbit f____________.
A. sme different cmets appearing several times
B. the same cmet appearing at different times
C. three different cmets appearing at the same time
D. several cmets appearing at the same time
5. Hailey made his discvery____________.
A. by ding experiments
B. by means f his wn careful bservatin
C. by using the wrk f ther scientists
D. by chance
6. When did Hailey make a surprising, but crrect predictin?
A. In 1704.
B. In 1705.
C. In 1706.
D. In 1707.
7. This passage in general is abut____________.
A. Hailey and ther scientists
B. the rbit f a cmet
C. Newtn and Hailey
D. Hailey and his discvery
C
Cming frm a brken hme n the mean streets, Quentin had been n the wrng side f the law influenced by secret sciety and drugs. He has risen and fallen many times，which is why his turn rund is all the mre inspiring.
Having gt ut f the secret sciety and later hnurably retired frm the Marines(海军陆战队），Quentin struggled with varius business adventures including running barber shps and dry cleaners. Wanting t ffer a healthier ptin, he started his first restaurant in 2001 in his hmetwn. Again, success was lasting nly a shrt time fr ver a decade. Determined t make a change and fcus n giving rather than succeeding, Quentin changed things up again. It was then that his life really began t turn arund.
Frm 2013，his restaurant, The Turkey Chp Grill, wuld clse fr the paying public every Mnday and nly ffer free fd t thse in need. He served great meals t ver 1，000 pr peple every day frm his wn pckets，giving ver 60，000 meals in tw years.
Mney, hwever, remained an issue with such kindness and s，Quentin tk a chance and appeared n Guy Fieri’s shw “Grcery Games” in 2015. The shw had retired sldiers frm fur military branches in a cking cmpetitin. Quentin wn. Quentin has invested his winnings back in feeding the pr. Frm 1,000 a day, he successfully fed 2，000 fr Thanksgiving that year. His cncept f fcusing n giving rather than winning had finally paid ff.
“West Humbldt Park has a large number f hmeless, and the drug prblem is terrible. I wanted t shw the cmmunity that peple care and give thse dwn n their luck an pprtunity t wn what’s gd fr them，starting with what they put in their bdies. And, maybe that might inspire them t d better in ther aspects f their lives. ”
8. What caused Quentin’s life t start t change?
A. The retirement frm the army.
B. The pullback frm the secret sciety.
C. The success f his first restaurant in 2001.
D. The decisin f giving back t his cmmunity.
9. Hw did Quentin vercme financial prblems in 2015?
A. By winning a cmpetitin.
B. By taking part in a sldiers’ club.
C. By rganising a cking cmpetitin.
D. By accepting dnatins frm retired sldiers.
10. Which f the fllwing wrds can best describe Quentin?
A. Kind and ambitius.
B. Cperative and generus.
C. Curius and prfessinal.
D. Curageus and humrus.
11. What can the reader learn frm his stry?
A. Mney talks.
B. East r west, hme is best.
C. A begun wrk is half ended.
D. Nthing is impssible t a willing heart.
D
A study has fund that a lifetime f regular exercise and activity can slw dwn the aging prcess (衰老过程）. Researchers say that getting lder shuld nt necessarily mean becming mre weak r sick. Their research shws that the devtin t a life f mvement and exercise may help us live nt nly lnger, but als mre healthily.
Fr their study, the researchers lked at tw grups. The first grup was made up f 125 nn-prfessinal cyclists between the ages f 55 and 79. This grup included 84 healthy men and 41 healthy wmen. This grup was called the “cyclists”.
Researchers then fund 130 ther peple t make up a secnd grup. Within this grup, 75 peple were aged frm 57 t 80. The ther 55 were between the ages f 20 and 36. The peple in this grup were als healthy，but they did nt exercise regularly. This grup was called the “ nn-exercisers Smkers，heavy drinkers f alchl and peple with ther health issues were nt included in the study.
Then, researchers gave bth grups a series f tests. They tested their muscle mass，muscular strength，percentage f bdy fat and the strength f their immune systems(免疫系统）. Then the researchers cmpared the results f the tw grups.
Results shwed that the cyclists did nt experience bdy changes usually regarded as a nrmal aging prcess. Fr example, they did nt lse muscle mass r muscular strength. Als, their bdy fat did nt increase with age.
The researchers als fund smething they had nt expected. The study shwed that the immune systems f the cyclists did nt age either.
The researchers advise us all t find the exercise that we like in ur lives.
12. Hw did the researchers carry ut the study?
A. By cmparisn.
B. Thrugh discussin.
C. With imaginatin.
D. By reasning.
13. Which f the fllwing is a result f the research?
A. The cyclists kept thin.
B. The nn-exercisers gained weight easily.
C. The cyclists，muscles remained strng with age.
D. The nn-exercisers usually had health prblems.
14. Which is an unexpected result fr the researchers?
A. The cyclists had the nrmal aging prcess.
B. The cyclists, immune systems didn’t age.
C. The cyclists lst nearly all their fat.
D. Everyne needed exercise in their lives.
15. Which f the fllwing can be the best title fr the text?
A. Healthy Peple Need Mre Exercise
B. Take Exercise, the Harder，the Better
C. Cycling Is the Best Way t Prevent Aging
D. A Lifetime f Exercise Slws the Aging Prcess
第二节
阅读下面短文，从短文后的选项中选出可以填人空白处的最佳选项。选项中有两项为多余选项。
Reasns yu shuld make time fr the sunset
Here’s why yu shuld cnsider making time t watch the sunset.
It can slw dwn time.
Seriusly, by witnessing the beauty f the sunset, yu can slw dwn yur perceptin (感知）f time. 16. ________Amazingly, by spending time lking at the vast sky, we，re actually empwering (使能够）urselves t regain cntrl f the clck.
It can prvide energy fr yu.
Even if yu have t g back t the ffice after yu watch that last sliver disappear belw the skyline，taking a few minutes ut f yur day t experience sme f the glden hur will be wrth it. 17. ________Often when we feel exhausted we reach fr a cup f cffee，but research suggests a better way t get energized is t cnnect with nature.
It will frce yu t put yur phne dwn.
When we regard the sunset as a special ccasin, we feel the urge t dcument and save it—as if keeping phts f its beauty will help us remember that wnderful feeling. 18. ________
It will inspire yu.
There’s a reasn why the sunset is a timeless and cnstant inspiratin fr pets, writers and rmantics—it is inspiring. Mahatma Gandhi bserved this pwer when he said，“When I admire the wnders f a sunset r the beauty f the mn, my sul expands in the wrship f the creatr. ”
19. ________
All f us are drawn t the sunset, but peple in a few special places really regard the sunset as a daily pprtunity t give thanks. 20. ________Crwds gather t cheer and applaud it, reinfrcing(加强）the idea that we shuld celebrate and be thankful fr each day.
A. Nature is fuel fr the sul.
B. It will help yu appreciate life’s gifts.
C. D yu draw inspiratin frm the sunset?
D. It will allw yu t exercise in a healthy way.
E. D yu feel like there aren’t enugh hurs in the day?
F. But if yu experience the sunset mre regularly, yu’ll n lnger see it thrugh a screen.
G. In places like Santrini, Greece, and Maui, Hawaii, the sunset is regarded as a nightly celebratin.
第二部分语言运用
第一节
阅读下面短文，从每题所给的A、B、C、D四个选项中选 出可以填入空白处的最佳选项。
It’s hard being an astrnaut’s sn. I 21，everybdy expects yu t be special r 22，but Fm just an average student.
I ften wnder 23 my father ever had a sn like me. I mean he’s s 24 and s gd at everything. S I used t dream abut ding smething spectacular (令人惊叹的）t 25 my father.
In ne class, my teacher 26 a Father’s Day essay cntest fr us and the winners’ essays wuld be read in frnt f all the parents and students. After schl I walked hme, 27 abut my father, wh I wuld write abut in my essay. He sat with me in the 28 when I was a little kid and had a nightmare. He 29 me with a new puppy at my eighth birthday party. T me, he wasn’t a wrld-famus astrnaut, but just my dad.
I wrte abut all these 30in my essay. One f ur neighburs said，“I 31yu’ll win the cntest，David. Yu’re the nly ne in twn whse father is an astrnaut. ” I didn’t want t win 32 because my father was an astrnaut.
I wn the secnd prize. When I finished reading my essay, the 33 applauded. I saw my father blwing his nse. Dad ndded t me, 34his thrat，and put his hand n my shulder. “Sn，this is the 35 mment f my life，” he said.
It was the prudest mment f my life, t. Maybe I’ll never be a great her r win a Nbel Prize，but just then，it was enugh just t be my father’s sn.
21. A. dubtB. sayC. knwD. believe
22. A. strangeB. hnestC. perfectD. frmal
23. A. whyB. whereC. whetherD. when
24. A. nrmalB. funnyC. specialD. unique
25 A. shckB. influenceC. attractD. impress
26. A. reprtedB. annuncedC. claimedD. warned
27 A. caringB. wrrying
C. thinkingD. cmplaining
28. A. silenceB. threat
C. hrrrD. dark
29. A. pleasedB. astnished
C. supprtedD. encurage
30. A. experiments B. incidents
C. dreams D. memries
31. A. wishB. guess
C. betD. prmise
32. A. merelyB. never C. hardlyD. nearly
33. A. parentsB. audienceC. studentsD. teachers
34. A. cleanedB. blewC. clearedD. pened
35. A. mstB. prudestC. smallestD. lngest
第二节
阅读下面短文，在空白处填入1个适当的单词或括号内单词的正确形式。
Back t the Mn
NASA is n a missin t put the first wman and the next man t the mn by 2024. On May 16，the space agency tk the 36. _________(late) step in that prcess. It annunced the 11 cmpanies 37. _________ (chse) t help prduce advanced human lunar landers. These spacecraft 38. _________ (use) t transprt astrnauts t the mn’s surface during a mn missin. NASA has named this missin Artemis, 39. _________ is the twin sister f Apll and gddess f the mn in Greek mythlgy.
NASA last sent peple t the mn n the Apll 17 missin. That was in 1972. Nw, the agency wants t learn40. _________humans can live there. NASA leader Jim Bridenstine ntes n the rganizatin’s website. “This time, when we g t the mn, we will stay. ” The 11 cmpanies NASA has wrked with will study human landing systems and develp mdels. “Our team is excited t get back t the mn as 41. _________ (quick) as pssible,” said Marshall Smith. He is directr fr human lunar 42. _________ (explre) prgrams at NASA. 43. _________ (wrk) with the cmpanies is “ an achieving that gal, he adds. The imprtant step” 44. _________ cmpanies have been chsen frm eight states. NASA 45. _________ (achieve) the cmpanies a ttal f $ 45. 5 millin s far.
第三部分写作
第一节
假定你是李华，最近某英文报社就“城市生活的利与弊”面向社会进行征稿，请你给报社编辑写一封信，谈谈自己的看法。要点如下：
Advantages
1. 交通便利 2. 有休闲场所
Disadvantages
1. 生活消费高 2. 人口多、拥挤
第二节（满分25分）
阅读下面短文，根据其内容写一篇60词左右的内容概要。
Wh is in cntrl f yur life? Wh is pulling yur strings? Fr the majrity f us, it’s ther peple—clleagues, friends r ur family, r even sciety. We learned this way f perating when we were very yung, f curse. We were brainwashed. We discvered that feeling imprtant and feeling accepted was a nice experience and s we learned t d everything we culd t make ther peple like us. As Oscar Wilde puts it, “Mst peple are ther peple. Their thughts are smene else’s pinins, their lives a mimicry (模仿)，their passins a qutatin. ”
When peple tell us hw wnderful we are，it makes us feel gd. We lng fr this gd feeling like a drug—we are addicted t it and seek it ut wherever we can. Therefre, we are s eager fr the apprval f thers that we live unhappy and limited lives， failing t d the things we really want t. Just as drug addicts and alchlics live wrsened lives t keep getting their drugs，we wrsen ur wn existence t get ur wn cnstant drugs f apprval.
But, just as with any drug, there is a price t pay. The price f the apprval drug is freedm—the freedm t be urselves. The truth is that we cannt cntrl what ther peple think. Everyne has a different way f thinking，and peple change their pinins all the time. Mrever, peple have their wn business，and in the end，they’re mre interested in themselves than in yu. The persn wh tries t please everyne will nly end up getting exhausted and prbably pleasing n ne in the prcess.
S hw can we take back cntrl? I think there’s nly ne way—make a cnscius decisin t stp caring what ther peple think. We shuld guide urselves by means f a set f values— nt values impsed (强力口）frm the utside by thers，but values which cme frm within. If we are driven by these values and nt by the changing pinins and value systems f thers, we will live a mre authentic, effective, purpseful and happy life.
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参考答案及解析：
第一部分阅读
第一节
【语篇导读】本文是一篇说明文。文章向我们讲述了随着新工具发明，天文学也随之发展。
1. D【解析】细节理解题。根据第二段中的“Theywatched the stars mve as the seasns changed. ”可知，当古希腊人看星空时，他们能 够观测到星星随着季节的变化而移动。故选D项。
2. A【解析】细节理解题。根据第三段的内容可知，直到有了望远 镜，人们才了解月球。故选A项。
3. D 【解析】细节理解题。根据第二段中的“But the Greeks had n tls t help themselves study the heavens. ”和第三段中的“They did nt knw that the planet called Saturn had rings arund it. ”可知，D 项 (2，000多年前，古希腊人认为土星周围有圆环）不符合文意。故选D项。
B
【语篇导读】本文是一篇记叙文，介绍了科学家哈雷及他是如何发现哈雷彗星的。4. B 【解析】细节理解题。根据第四段中的“ He cncluded that they had simply seen the same cmet three times. ”及上文提到的看到彗星的时间分别是1531年、1607年和1682年可知，B项正确。
5. C 【解析】细节理解题。根据第一段中的“ He studied the bservatins f cmets which ther scientists had made. ” 以及第二段 中的“He figured ut the rbits . . . by scientists. ”可知，哈雷的发现是在研究其他科学家们的观测结果时得出来的。故选C项。
6. B【解析】细节理解题。根据最后一段中的“He decided that this wuld appear in the year 1758. There were 53 years t g befre Hailey’s predictin culd be tested. ”可知，哈雷预测曾星会在 1758 年出现，而这需要过53年才能得到验证，即1758 -53 = 1705,故选 B项。
7. D【解析】主旨大意题。通读全文可知，本文主要介绍了科学家哈 雷及他是如何发现哈雷彗星的。故选D项。
C
【语篇导读】本文是一篇记叙文。文章主要讲述了昆廷经历起起伏伏的人生，最终取得成功的故事。
8. D【解析】细节理解题。根据第二段中的第四句可知，昆廷把重心放在回报社会的决定让他的人生开始转变。故选D项。
9. A 【解析】细节理解题。根据第四段中的“The shw had retired sldiers frm fur military branches in a cking cmpetitin. Quentin wn. ”可知，昆廷在一场厨艺大赛中获胜，解决了他的资金问题。 故选A项。
10. A 【解析】推理判断题。根据昆廷回报社会的做法，可知他是善良的，并且他失败了也不放弃，为自己的目标继续努力，可推知他是有抱负的。故选A项。
11. D【解析】推理判断题。本文主要讲述了昆廷经历起起伏伏的人生,最终取得成功的故事，这个故事告诉我们:有志者事竟成。故选D项。
D
【语篇导读】本文是一篇说明文。文章介绍了一项研究发现终身有规律地锻炼和运动可以减缓衰老过程。
12. A 【解析】细节理解题。根据第二段至第六段可知,研究人员设立了两个对比小组并比较了两组的结果，即研究人员通过比较来进行研究。故A项正确。
13. C【解析】细节理解题。根据第五段中的“Results shwed that the cyclists did nt experience bdy changes . . . they did nt lse muscle mass r muscular strength. 可知，研究结果显示，骑自行车的人没 有随着年龄的增长而失去肌肉含量和肌肉力量,也就是说骑自行 车的人的肌肉依然保持强健。故C项正确。
14. B【解析】细节理解题。根据倒数第二段可知，令研究人员没有 想到的是，骑自行车的人的免疫系统也没有老化。故B项正确。
15. D【解析】标题归纳题。根据第一段第一句“A study has fund that a lifetime f regular exercise and activity can slw dwn the aging prcess. ”以及下文内容可知，本文主要介绍了一项研究发现终身有规律地锻炼和运动可以减缓衰老过程。故D项最适合作为本文标题。
第二节
【语篇导读】本文是一篇说明文。文章列举了五个应该抽时间去看日落的理由。
16. E【解析】 根据上文中的“Seriusly，by witnessing the beauty f the sunset, yu can slw dwn yur perceptin f time. ”可推知，看日落时我们对时间的感知会变慢。故E项（你觉得一天没有足够的时间吗？）符合语境。故选E。
17. A【解析】根据小标题“ It can prvide energy fr yu. ”可知，本段讲的是日落能给人提供能量，而日落属于大自然的景象，故选A。 A项中的nature与空后句子中的nature相呼应，fuel与小标题中 的energy相呼应。
18. F 【解析】根据上文中的“When we regard the sunset as a special ccasin . . . remember that wnderful feeling. ” 以及本段小标题“It will frce yu t put yur phne dwn. ” 可知，F 项（但是如果你更经常地看日落,你就不会再通过屏幕看它了）符合语境。故选F。
19. B【解析】空处为小标题，根据F文中的“All f us are drawn t the sunset，but peple in a few special places really regard the sunset as a daily pprtunity t give thanks. ”可推知，日落会帮助你感激生活的给予。故选B。
20. G 【解】 下文中的“ Crwds gather t cheer and applaud it, reinfrcing the idea that we shuld celebrate and be thankful fr each day. ”中celebrate可对应到G项中的celebratin，G项（在希腊的 圣托里尼岛和夏威夷的毛伊岛等地，日落被视为夜间的庆祝活 动）符合语境。故选G。
第二部分语言运用
【语篇导读】作为一名宇航员的儿子，作者被很多人羡慕着并且被期望与众不同，作者过去也总想着做些引人注意的事情让父亲印象深刻. 但是通过一次作文比赛作者认识到，只要做爸爸的儿子就足够了。
21. C 【解析】根据前一句 “It’s hard being an astrnaut’s sn. (做~-名 宇航员的儿子真难）”可知，此处指的是“我知道，每个人都盼望着你很特别或十全十美”。故选C项。
22. C 【解析】第一句说做宇航员的儿子难,此处解释难的原因：每个人都盼望着你很特别或十全十美。根据r前的special可知选C 项。perfect意为“完美的”，符合语境。
23. A 【解析】 根据后一句 “I mean he’s s _ and s gd at everything. ”可知,作者总是想知道父亲为什么会有像他这样的儿子。故选A项。
24. C【解析】根据第一段第二句中的“everybdy expects yu t be special r”和该空后的s gd at everything可知，作者认为父亲很特别，special意为“特别的”。故选C项。
25. D 【解析】根据该空前的ding smething spectacular可知此处指 的是作者想做一些惊人的举动来给父亲留下深刻的印象。 impress sb意为“给某人留下深刻的印象”。故选D项。
26. B 【解析】根据空后的a Father’s Day essay cntest可知，作者的老师宣布了一个有关父亲节的写作比赛。annunce意为“宣布”。 故选B项。
27. C 【解析】结合语境可知此处指的是,作者在回家的路上，一边走一边想自己的父亲。think abut意为“考虑;思考”。故选C项。
28. D【解析】根据空后的had a nightmare可知此处指的是，当作者是个小孩子，做噩梦的时候，父亲会坐在黑暗当中陪伴作者。故选 D项。
29. A【解析】此处指的是,他用一条新的小狗来逗作者开心。please 意为“使高兴”。故选A项。
30. D 【解析】根据上一段的描述可知，作者把所有这些记忆都写在了文章当中。memry意为“记忆”。故选D项。
31. C【解析】根据后一句“Yu’re the nly ne in twn whse father is an astrnaut. ”可知,邻居打赌说作者会在比赛中获胜。bet意为 “打赌;敢说”。故选C项。
32. A【解析】句意:我不想只是因为我爸爸是宇航员而获胜。根据上下文语境可知选A项。merely意为“仅仅;只不过”。
33. B【解析】根据第三段的描述可知，台下除了学生以外，还有老师和家长。故此处指的是观众鼓起掌来。audience意为“观众”。 故选B项。
34. C【解析】根据上文中的“I saw my father blwing his nse. ” 可知， 父亲擤了擤鼻子,此处则应指他清了清嗓子,把手放在作者的肩膀上对作者说。clear ne's thrat意为“清嗓子”。故选C项。
35. B 【解析】 根据下文中的“It was the prudest mment f my life, t. ”可知，此处指的是这是父亲最骄傲的时刻。故选B项。
第二节
【语篇导读】本文是一篇说明文。文章主要讲述了NASA计划在；2024年将第一位女性和下一位男性送往月球。
36. latest【解析】此处表示在那个过程中有了最新的进展，需用late 的最高级形式latest。
37. chsen 【解析】11 cmpanies与chse之间是逻辑上的动宾关系， 故用过去分词作后置定语。
38. are used 【解析】these spacecraft与use之间是被动关系，此处又是描述一个客观事实,故用一般现在时的被动语态。
39. wh 【解析】先行词Artemis是人,关系词在后面的非限制性定语 从句中作主语，故用wh。
40. if/whether【解析】learn后是宾语从句，此处表示想了解人类是否 能居住在月球上，故用if/whether引导宾语从句。
41. quickly【解析】修饰动词短语get back t应用副词形式。
42. explratin【解析】用名词explratin修饰名词prgrams,以说明 prgrams的性质。
43. Wrking【解析】谓语动词是is，其前应用动词-ing作主语。
44. t【解析】空后是动词-ing形式，前面应用介词。a step t ding sth做某事的一步。
45. has achieved 【解析】根据句中的时间状语s far可知谓语动词应 用现在完成时。
第三部分写作
第一节
One pssible versin：
Dear editr,
I’m writing t yu t talk abut the advantages and disadvantages f living in the city.
Sme peple are in favur f living in the city. In their view, there are always many chices f public transprt. Besides, they can g t the cinemas and parks whenever they want t relax.
Others，hwever，are against the idea，firmly believing living cst in the city is much higher. What，s mre, the city is crwded and nisy. It is very difficult t find a place where peple can enjy peace.
Persnally speaking，with the develpment f ecnmy，living in the city is a must fr peple. We must make great effrts t reduce pllutin and make the city mre beautiful.
Yurs,
Li Hua
第二节
One pssible versin：
It is cmmn that ur life is cntrlled by ther peple arund us. (要点 1 ) That’s because we attach great imprtance t being apprved f by them. (要点 2) Sadly, their recgnitin csts us ur freedm t be wh we are，whereas their changeable and uninterested thughts are uncntrllable. (要点 3) Hwever, we can still be ur wn masters by ignring pinins f thers and sticking t ur inner values, thus making ur life cheerful and meaningful. (要点 4)