Unit 6 Earth first单元综合检测（含解析）高中英语外研版（2019）必修 第二册

单元综合检测(六)
第一部分　阅读
第一节
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
Endangered Species Books for Kids
Will We Miss Them Endangered Species
Written from the unique view of a 13 year old author，this book interests children in the lives and challenges of endangered species，helping other young people learn about these animals as the first step towards saving them．
◆Author: Alexandra Wright
Almost Gone: The World's Rarest Animals
Have you ever seen a wombat or an Eastern barred bandicoot Probably not．These animals are almost gone from the earth，and they're not alone．Simple，informative text and cul paper paintings introduce basic endangered species knowledge to young children．
◆Author: Steve Jenkins
A Poetic Journey into the Wild
Take a journey across land and sea to meet 21 endangered and threatened animals．Lovely paintings and poems introduce amazing animals from around the globe and show the dangers they face．The book also lists activities and organizations that provide more detailed information about endangered species protection．
◆Author: Rachel Allen Dillon
Eyewitness: Endangered Animals
This DK Eyewitness book is an exploration of endangered animals around the world，including factors that are driving them towards extinction and ways that we can help them survive．Blocks of text and diverse photographs keep readers turning the pages．
◆Author: Ben Hoare
1．Which book is written by a teenage author
A．A Poetic Journey into the Wild．
B．Eyewitness: Endangered Animals．
C．Almost Gone: The World's Rarest Animals．
D．Will We Miss Them Endangered Species．
2．What can we find in A Poetic Journey into the Wild
A．Activities of hunting wildlife．
B．Poems about amazing animals．
C．Paintings about some extinct animals．
D．Surroundings of the endangered wildlife．
3．What is the purpose of the text
A．To list some endangered animals．
B．To encourage protection of animals．
C．To introduce endangered species books．
D．To call on readers to fight illegal hunting．
B
Chen Guanghui is a guardian for black necked cranes(黑颈鹤) in the Dashanbao Black necked Crane National Nature Reserve of Zhaotong city，in southwest China's Yunnan Province．Whistling(吹口哨) is the secret language Chen uses to communicate with the black necked cranes，a type of migratory bird under first class protection in China．She says different whistles signal different things．When she whistles in an increasing tone，she tries to tell the cranes: ask your companions to come back for lunch，and they would chirp(吱喳叫) to spread the message right away．
Living near the Dashanbao Nature Reserve，a major winter habitat(栖息地) for the rare species，Chen started to take care of them in 2003，a mission she took over from her mother，whose devotion dates back to the 1990s．
“In the first few days，I remembered they ran away as soon as I approached them．I was very upset and asked my mum to come back，and I was worried they would starve，” says Chen．“I initially tried everything，even singing folk songs to attract them，but failed．Later，I used special whistles and gradually formed close bond with the cranes．”
“I treat them as if they were my own children，and I'm always concerned about them，especially during snowy days when they can't get food．I feel uncomfortable and anxious when I hear them chirp and usually rush to prepare corn for them．” It's never been an easy job，and Chen has sustained quite a few injuries over the years，even falling into frozen marsh(沼泽) while trying to save a trapped crane in 2008．However，she never gave up．With love and responsibility，she has persisted in caring for the cranes for about 20 years．
Thanks to the joint protection efforts of Chen and staff members at the nature reserve，now more than 1，900 black necked cranes overwinter in the area each season every year，up from about 300 when the nature reserve was established．
4．How does Chen Guanghui communicate with black necked cranes
A．By singing folk songs．
B．By imitating chirps of birds．
C．By making hand gestures．
D．By blowing special whistles．
5．What does the underlined word “mission” in paragraph 2 refer to
A．Rescuing injured animals．
B．Restoring habitats for rare species．
C．Looking after black necked cranes．
D．Building Dashanbao Nature Reserve．
6．How did Chen Guanghui feel about her initial attempts at the work
A．It is inspiring．
B．It is frustrating．
C．It is interesting．
D．It is exciting．
7．What can we learn from Chen's story
A．Efforts bear fruit．
B．Fortune favours the brave．
C．Virtue is its own reward．
D．A miss is as good as a mile．
C
Like human armies，army ants smoothed out anything in their path．They make a habit of finding foods，often much larger than themselves，breaking them into pieces and dragging the pieces back to their camps．But they do not eat them out，with their army bases full of rubbish．But little is known about which kind of animals feed on army ants' leavings．Christoph von Beeren at the Technical University of Darmstadt and Daniel Kronauer at the Rockefeller University in New York went to the rainforests of Costa Rica to find out．They found a whole ecosystem depends on the leftovers(残留食物) to survive．
Watching little insects in a rainforest is much tougher—these cleaners had not been examined before．But the researchers hoped modern DNA analysis techniques might make the job easier．Working with a team of co workers，they followed ants back to their camps，finding 34 places in total．
The researchers collected all the insects at each place and brought them back to laboratory．In total，they collected 8，364 adult beetles(甲壳虫)，511 beetle babies and 24 beetle eggs．Those were spread across 91 species，several of which were new to science．Far beyond what anyone had expected，these figures suggest that the leftovers are not fast food restaurants but homes，where the beetles live from birth to death．
How these species manage to avoid being eaten by their army ant hosts is still a mystery．Dr Von Beeren guessed that it partly depends on the fact that ants need them to keep their camps clean or partly depends on the fact that many species of beetles are able to produce chemicals that smell bad to ants．
The research only has shown a little of what is going on in the rubbish．Besides beetles，there were other kinds of insects that the team simply did not have time to study and they were of equal importance to their study according to Dr Daniel Kronauer．
8．Why did the researchers go to the rainforest
A．They wanted to study ants．
B．They wanted to prove their arguments．
C．They wanted to solve the mystery．
D．They wanted to enjoy nature．
9．What can we learn from the passage
A．All the beetles found were already known．
B．Modern techniques did make the job easier．
C．It was easy for people to study insects in forest．
D．Not just beetles fed on the left foods to survive．
10．What might the researchers do next
A．To study other insects feeding on ants' leftovers．
B．To find more about the life of ants in the rainforests．
C．To make further study on beetles feeding on ants' leftovers．
D．To find more about the ecosystem in the rainforests．
11．Where does this passage probably come from
A．A geographic magazine．
B．A fashion column．
C．A science fiction．
D．A scientific journal．
D
The endangered pandas in Qinling Mountains might face a new threat: the loss of their food，bamboo，which makes up 99% of their meals．
Adult pandas spend most part of the day eating bamboo and have to take in at least 40 pounds a day to stay healthy．However，a new study published in Nature Climate Change warned that they may soon find their food gone because most of the bamboo in Qinling Mountains might disappear by the end of the century as a result of rising temperature worldwide．
A team made up of researchers from Michigan State University and the Chinese Academy of Sciences has studied the effects of climate change on the bamboo in Qinling Mountains．They have found that bamboo is very sensitive to climate change．“80% to 100% of the bamboo would be gone if the average temperature increases 3.5 degrees worldwide by the end of the century，” said Liu Jianguo，one of the report's authors．
He added，“This is how much the temperature would rise by 2100 even if all countries will keep their promises in the Paris Agreement．But you know what is happening around the world．”
In recent years，China has been trying its best to protect the endangered pandas by setting up more and bigger natural reserves．
“But it is far from being enough and the endangered pandas need cooperation from the rest of the world，because their future is not just in the hands of the Chinese，” said Shirley Martin from World Wildlife Fund but not a member of the team．
The Qinling Mountains，in the southwest of China，are home to about 260 pandas．That is about 13% of the China's wild panda population．In addition，about 375 are living in research centers and zoos in China．
12．What can we learn from the first paragraph
A．Lots of the bamboo in Qinling Mountains will probably disappear．
B．Qinling Mountains cannot provide enough bamboo for the pandas．
C．Pandas in Qinling Mountains are just threatened by the loss of food．
D．Pandas have already eaten 99% of the bamboo in Qinling Mountains．
13．What does Liu Jianguo mean
A．China needs more help from World Wildlife Fund．
B．Bamboo is sensitive to the changes of temperature．
C．China is making great efforts to protect the pandas．
D．It is difficult to control the temperature rise within 3.5℃．
14．How many wild pandas are there in China
A．About 260． B．About 635．
C．About 2，000． D．About 2，635．
15．Which can be the best title for the text
A．The Disappearance of Bamboo
B．Necessity to Change Pandas' Food
C．Efforts Made to Save Pandas
D．A New Threat Faced by the Pandas
第二节
阅读下面短文，从短文后的选项中选出可以填入空白处的最佳选项，选项中有两项为多余选项。
Trees around us are extremely important and have always been necessary for improving the human conditions．Our existing forests and trees we plant work to make a better world． 16 ． Here is a short list of main reasons why trees are necessary for improving our living conditions．
·Trees produce oxygen
17 ．A leafy tree produces as much oxygen in a season as ten people inhale(吸入) in a year．What many people don't realize is that the forest also acts as a giant filter(过滤器) that cleans the air we breathe．Trees help clean the air by preventing airborne particles，reducing heat，and absorbing such pollutants．
·Trees clean the soil
The term phytoremediation(植物修复) is a fancy word for the absorption of dangerous chemicals and other pollutants that have entered the soil． 18 ．Trees filter sewage and farm chemicals，reduce the effects of animal wastes，clean roadside spills and so on．
·Trees are carbon sinks
To produce its food，a tree absorbs and locks away carbon dioxide in the wood，roots and leaves．Carbon dioxide is a global warming suspect． 19 ．This locking up process “stores” carbon as wood and not as a “greenhouse” gas．
20
Trees block urban noise almost as effectively as stone walls．Trees，planted at strategic points in a neighborhood or around your house，can reduce major noises from freeways and airports．
A．Trees help clean the sky
B．Trees control noise pollution
C．We could not exist as we do if there were no trees
D．Man has been planting trees to make the planet a more beautiful world
E．A forest is a carbon storage area that can lock up as much carbon as it produces
F．The modern human community has other more practical reasons to admire and honour trees
G．Trees can either store harmful pollutants or change the pollutants into less harmful forms
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。
The victims were carried in one by one，their paws and fur burned，suffering from dehydration(脱 水)and fear．Their caretakers 21 their wounds，and 22 them in baskets with the only thing that was 23 — the leaves of eucalyptus(桉树) trees．As miserable fires have 24 more than 2 million acres in Australia，only dozens of koalas have been 25 from the smoky trees and 26 ground．
Koalas，unlike kangaroos，birds or snakes，do not 27 from fires but instead climb trees to the top，where they can curl themselves into a ball for 28 and wait for the danger to 29 ．
But during big fires，such as those that have burned in recent weeks，the animals are far less likely to 30 ．Even if the fire itself does not reach the tree 31 ，the animals may over heat and fall to the ground，where they can be burned to death．
The tough situation of the koala has raised 32 among scientists and conservationists(环保主义者)．While koalas have developed to exist alongside the wildfires，they are facing new 33 ，not just from climate change but also from human development，which has dislocated koalas' populations， 34 their ability to survive fires．
We have these 35 animals not found anywhere else on this planet，and we are killing them．This is a big wake up call．
21．A．touched B．treated
C．ignored D．discovered
22．A．threw B．locked
C．laid D．forced
23．A．familiar B．plentiful
C．beautiful D．expensive
24．A．reached B．left
C．burned D．trapped
25．A．killed B．recognized
C．hurt D．rescued
26．A．flat B．black
C．broad D．safe
27．A．escape B．die
C．suffer D．rise
28．A．balance B．protection
C．challenge D．comfort
29．A．attack B．come
C．pass D．avoid
30．A．jump B．climb
C．fall D．survive
31．A．top B．leaves
C．trunk D．root
32．A．passion B．concern
C．fear D．interest
33．A．chances B．choices
C．neighbors D．threats
34．A．weakening B．developing
C．enriching D．ensuring
35．A．lonely B．stupid
C．lazy D．unique
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。
A rainforest is an area 36．__________(cover) by tall trees with the total high rainfall spreading quite equally through the year．Rainforests have a great effect on the world environment because they can take in heat from the sun and adjust it to the climate．37．__________ the forest cover，these areas would reflect more heat into the atmosphere，38．__________(warm) the rest of the world．Losing the rainforests may also influence wind and rainfall patterns，potentially causing certain natural disasters all over the world．
In the past hundred years，humans 39．__________(begin) destroying rainforests in search of three major resources: land for crops，wood for paper and other products，and land for raising farm 40．__________(animal)．This action affects the environment as a whole．For example，a lot of carbon dioxide in the air comes from burning the rainforests．We 41．__________(obvious) have a need for the resources we gain from cutting down trees，42．__________ we will suffer much more than we will benefit．
Rainforests are often called the world's drugstore．More than 25% of the medicines we use today come from plants in rainforests．However，fewer than 1% of rainforest plants have been examined for their 43．__________(medicine) value．It is extremely likely 44．__________ our best chance to cure diseases 45．__________(lie) somewhere in the world's shrinking rainforests．
第三部分　写作
第一节
假定你是李华，是校英文报的记者。你校在10月4日“世界动物日”那天组织了一系列相关活动。请你就此写一篇新闻报道，内容包括：
1．活动目的；
2．活动内容；
3．活动反响。
注意：1．词数80左右；
2．可适当增加细节，以使行文连贯。
Animal Protection Activities Held
_________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________第二节
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。
Puppies for Sale
A little boy lived in a small town of Northern California called Oxnard．He was a lovely boy but he lost his left leg in a car accident and had to walk by a false leg(假肢)．He couldn't follow other kids．He felt lonely and decided to keep a pet dog as his friend．
One day，he walked past a pet shop and saw a sign above the door that said，“Puppies for Sale”．The little boy asked the shop owner，“I want to buy one of your puppies．Can I please look at the puppies？”
The pet shop owner got impressed with the honesty of the boy．“Sure，” said the shop owner．He smiled and whistled loudly．Five puppies ran down the walkway of the pet shop．
The little boy's eyes danced with pleasure．As the puppies made their way towards the fence，the little boy noticed that one puppy was falling behind．This puppy was limping (跛行) and trying its best to catch up the others．
Immediately the little boy pointed out towards the limping puppy and asked，“What's wrong with that little puppy？” The shop owner explained that when the puppy was born，the pet hospital had examined the little puppy and had discovered there was something wrong with its back leg．It would limp for the rest of his life．
The little boy got really excited and said，“That is the puppy that I want to buy．” The shop owner replied，“No，that puppy is not for sale．Nobody will buy that puppy due to his disabled leg．If you really want him，I'll just give him to you for free．”
注意：1．续写词数应为150左右；
2．请按如下格式作答。
The little boy got quite upset with the reply of the shop owner．__________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
However，the boy decided to buy the little puppy and thought that he should pay for it．
_______________________________________________________________________________________________________________________________________________________________________________________________________________
单元综合检测(六)
1 2 3 4 5 6 7 8 9 10 11 12
D B C D C B A C D A D A
13 14 15 16 17 18 19 20 21 22 23 24
D C D F C G E B B C A C
25 26 27 28 29 30 31 32 33 34 35
D B A B C D A B D A D
36．covered　37．Without　38．warming　39．have begun　40．animals　41．obviously　42．but/yet　43．Medical 44．that　45．lies
第三部分　第一节
[参考范文]　
Animal Protection Activities Held
To raise our awareness of protecting animals，our school held diverse activities on October 4th，“World Animal Day”．
A photo exhibition attracted a number of students，showing us many animals are becoming endangered species for various reasons like illegal hunting and pollution．More inspiring was a speech contest where participants eagerly talked about how we individuals could make a difference．
The activities turned out a great success．As one student put it，“It's really distressing to see the animals dying out at such an alarming rate．It's time we should spare no effort to protect them．”
第二节
[参考范文]
The little boy got quite upset with the reply of the shop owner． He looked straight into the shop owner's eyes and said，“I don't want you to give him to me．That little dog is worth every bit as much as all the other dogs，and I'll pay full price．” The shop owner tried to persuade the boy to stop buying the puppy and said，“You really want to buy this little dog He is never going to be able to run and jump and play with you like the other puppies．”
However，the boy decided to buy the little puppy and thought that he should pay for it． The shop owner asked，“Why do you want this dog？” To the shop owner's surprise，the little boy reached down and pulled up his pant leg to show his false left leg supported by a big metal brace．He looked up at the shop owner and softly replied，“Well，I don't run so well myself，and the little puppy will need someone who understands！” The pet owner was moved by his words．Finally they reached an agreement that the boy paid for the little puppy and brought it home happily．
【语篇解读】　本文是一篇应用文。文章介绍了几本适合儿童读的关于濒危物种书籍的相关信息。
1．D　[细节理解题。根据Will We Miss Them Endangered Species中的“Written from the unique view of a 13yearold author，this book interests children in the lives and challenges of endangered species”可知，Will We Miss Them Endangered Species是由一位少年作家所写的。故选D项。]
2．B　[细节理解题。根据A Poetic Journey into the Wild中的“Lovely paintings and poems introduce amazing animals from around the globe and show the dangers they face．”可知，在《诗意的荒野之旅》中我们能发现关于神奇动物的诗。故选B项。]
3．C　[推理判断题。根据文章标题“Endangered Species Books for Kids”以及下文对四本书籍内容及作者的介绍可知，短文的写作目的是介绍适合儿童读的关于濒危物种书籍。故选C项。]
【语篇解读】　本文是一篇记叙文。文章讲述了陈光惠保护黑颈鹤的故事。
4．D　[细节理解题。根据第一段中“Whistling is the secret language Chen uses to communicate with the blacknecked cranes，a type of migratory bird under firstclass protection in China．”可知，吹口哨是陈和黑颈鹤的交流方式。故选D。]
5．C　[词义猜测题。根据第二段中“Chen started to take care of them in 2003，a mission she took over from her mother，whose devotion dates back to the 1990s．”可知，mission指的是她从母亲手里接过来的任务。故选C。]
6．B　[推理判断题。根据第三段中“I initially tried everything，even singing folk songs to attract them，but failed．”可以判断，陈对最初的尝试是沮丧的。故选B。]
7．A　[推理判断题。根据最后一段“Thanks to the joint protection efforts of Chen and staff members at the nature reserve，now more than 1，900 blacknecked cranes...up from about 300 when the nature reserve was established．”可知，陈的努力带来了积极的效果。故选A。]
【语篇解读】　本文是一篇说明文。文章主要讲述了科学家研究哪种动物以行军蚁的残余食物为食并得到新的发现。
8．C　[细节理解题。根据第一段中“But little is known about which kind of animals feed on army ant leavings...went to the rainforests of Costa Rica to find out．”可知，研究者去雨林是为了解决秘密——哪种动物以行军蚁的残余食物为食。故选C项。]
9．D　[细节理解题。根据最后一段中“Besides beetles，there were other kinds of insects that the team simply did not have time to study and they were of equal importance to their study according to Dr Daniel Kronauer．”可知，除了甲虫，还有其他昆虫以行军蚁的残留食物为食。故选D项。]
10．A　[推理判断题。根据最后一段中“Besides beetles，there were other kinds of insects that the team simply did not have time to study and they were of equal importance to their study according to Dr Daniel Kronauer．”可知，研究者接下来应该会研究其他以蚂蚁残留食物为食的昆虫。故选A项。]
11．D　[文章出处题。根据第一段以及后文可知，文章主要讲科学家研究哪种动物以行军蚁的残余食物为食并得到新的发现。所以这篇文章可能摘自一本科学期刊。故选D项。]
【语篇解读】　本文是一篇说明文。文章介绍了生活在秦岭一带的大熊猫将面临一个新的威胁：赖以生存的竹子会因为全球温度升高而消失。
12．A　[细节理解题。根据第一段可知，秦岭的大部分竹子也许会遭遇灭顶之灾，可能会消失。故选A项。]
13．D　[推理判断题。根据第四段中刘建国说的“This is how much the temperature would rise by 2100 even if all countries will keep their promises in the Paris Agreement．But you know what is happening around the world．”可知，即使所有国家都遵守《巴黎协定》中的承诺，到2100年，全球气温仍然会增加3.5摄氏度。由此推知，刘建国认为控制温度上升在3.5摄氏度以内是很难的事情。故选D项。]
14．C　[细节理解题。根据最后一段中“The Qinling Mountains，in the southwest of China，are home to about 260 pandas．That is about 13% of the China's wild panda population．”可知，中国野生大熊猫总数是：260÷13%＝2000。故选C项。]
15．D　[标题归纳题。根据第一段以及全文可知，本文主要讲述了生活在秦岭一带的大熊猫将面临一个新的生存威胁：赖以生存的竹子将会消失。D项“大熊猫面临的新威胁”符合题意。故选D项。]
【语篇解读】　本文是一篇说明文。文章介绍了树木对人类生存环境所起的重要作用。
16．F　[空前提到，地球上的自然林和我们种植的树木一起创造更好的世界；空后提到，这里有一份简单列表，列出了树木对改善我们的生存环境非常必要的主要原因。故F项“当今的人类社区还有其他更现实的理由钦佩、珍视树木”承上启下，符合语境。]
17．C　[根据下文可知，此处是说树所产生的氧气帮助我们存活，故C项“如果没有树木我们就不能生存”符合语境。]
18．G　[根据空后的内容可知，树木会过滤污水和农业用药，减少动物粪便的影响及清理路边的污物等，故G项“树木要么储存有害的污染物，要么将污染物转化为危害较小的形式”承上启下，符合语境。]
19．E　[根据空前的“locks away carbon dioxide”和空后的“This lockingup process ‘stores’ carbon”可知，E项“森林是一个碳储存区，可以储存其产生的尽可能多的碳”符合语境。]
20．B　[结合本段内容可知，此处讲的是树木可以减少噪声污染，故B项“树木控制噪声污染”符合语境。]
【语篇解读】　本文是一篇记叙文。澳大利亚的一场大火造成许多动物受伤，其中考拉伤亡严重，这次火灾警示世人要保护动物。
21．B　[根据上文可知，它们被火烧伤了，根据“caretakers”可知，是对伤口进行治疗。故选B。]
22．C　[它们受伤了，医护人员治疗后会小心地把它们放到篮子里。故选C。]
23．A　[根据下文可知，这些受伤的动物是考拉，故它们对桉树的叶子是熟悉的。故选A。]
24．C　[根据“miserable fires”可知，是燃烧。故选C。]
25．D　[根据上文护理人员治疗考拉可知，是考拉从大火中被营救。故选D。]
26．B　[根据上文可知，火灾十分严重，树林里烟雾弥漫，大地被烧焦，因此是黑色的。故选B。]
27．A　[根据下文可知，考拉只能爬到树顶保护自己，因此说它们不像袋鼠、鸟类或者蛇那样能从火灾中逃脱。故选A。]
28．B　[在火中，它们爬上树顶，蜷缩成一团是为了保护自己。故选B。]
29．C　[考拉不像袋鼠、鸟类或者蛇那样逃脱，它们只能爬上树顶，蜷缩成团，等着火灾的结束。故选C。]
30．D　[根据下文可知，即使火没有烧到树顶，动物们也会因为过热掉落到地上被烧死。所以它们很难存活。故选D。]
31．A　[根据前文可知，考拉是爬到树顶躲避大火。故选A。]
32．B　[考拉遭遇了火灾，科学家和环保主义者应该是担忧的。故选B。]
33．D　[上文提到的野火对考拉来说是生存的威胁可知，下文提到气候变化，人类发展是它们面对的新的威胁。故选D。]
34．A　[根据上文可知，人类的发展是考拉面对的新的威胁，带来的是不好的影响，因此是削弱了考拉的生存能力。故选A。]
35．D　[根据下文“not found anywhere else on this planet”可知，这些动物是独一无二的。故选D。]
【语篇解读】　本文是一篇说明文。文章主要介绍了雨林的作用、人们破坏雨林的原因和造成的影响等。
36．covered　[考查非谓语动词。分析句子结构可知，设空处应用非谓语动词作定语，修饰an area，它与area之间是逻辑上的动宾关系，所以应用过去分词。故填covered。]
37．Without　[考查介词。句意：没有雨林覆盖的话，这些区域反射到大气中的热量会更多，从而使地球其他区域变暖。由句意可知，此处应用介词without。因其位于句首，故首字母大写。]
38．warming　[考查非谓语动词。设空处应用非谓语动词作结果状语，它与其逻辑主语(设空前描述的这件事)之间是主动关系，所以应用动词ing形式。故填warming。]
39．have begun　[考查动词的时态。根据本句中的时间状语“In the past hundred years”及下文内容可知，此处表示发生在过去，且对现在仍有影响的动作，故用现在完成时。]
40．animals　[考查名词复数。animal是可数名词，根据语境可知，此处应用animal的复数形式表泛指。故填animals。]
41．obviously　[考查副词。设空处修饰整个句子，应用obvious的副词形式。故填obviously。]
42．but/yet　[考查连词。句意：很明显，我们需要那些我们从砍伐树木中所获得的资源，但是我们因此遭受的苦难要比我们所获得的益处多得多。根据句意可知，前后两个分句之间为转折关系，故用but/yet。]
43．medical　[考查形容词。设空处作定语，修饰名词value，应用medicine的形容词形式，故填medical。]
44．that　[考查强调句型。本句中的“It”作形式主语，后面的从句作真正的主语，因为从句中不缺少成分且意思完整，所以此处应用that。]
45．lies　[考查时态和主谓一致。lie是从句的谓语动词，根据上下文语境可知，此处应用一般现在时；又因从句的主语的中心词chance是单数，此处谓语应用第三人称单数形式，故填lies。]
2 / 2