Unit 5Starting out & Understanding ideas 课件 -(2022）新外研版高中选择性必修第二册《英语》.pptx

1、Unit 5 A delicate worldStarting out Understanding ideasStarting out1.Watch the video and answer the questions.1)Are humans part of Earths ecosystems?Why?2)In what ways can humans affect ecosystems?Starting out2.Look at the satellite images and answer the questions.1)What is happening to the area acc

2、ording to the satellite images?2)What do you think a later satellite image would show?3)What do you think caused these changes?The water area is shrinking.The water area will be smaller.Perhaps because of human over-exploitation.The Aral SeaThe Aral Sea lies between Uzbekistan(to the south)and Kazak

3、hstan(to the north).Once the fourth largest lake in the world,the Aral Sea is now less than half of its original size.The Aral Sea is a terminal,or endorheic,sea(meaning no water flows out of it).It is fed by the Syr Darya and the Amu Darya Rivers,but Soviet river diversions for irrigation made over

4、 40 years ago have starved the Aral Sea of water.In 2001,the World Bank funded the construction of an 8-mile dam to separate the North and South Aral,and thereby save the smaller and less polluted North Aral Sea.The North Aral has been growing since completion of the Kok-Aral Dam in the summer of 20

5、05.Repairs and updates to the inefficient Soviet-era canals have also played a role in the rejuvenation of the North Aral.Understanding ideas Before reading 1.Look at the picture and answer the questions.1)What animals can you see in the picture?2)What kind of changes would take place if cats,rats a

6、nd rabbits were introduced to an environment like this?Penguins,and a bird.Understanding ideasUnderstanding ideas While reading words1.chaos n.大混乱；紊乱大混乱；紊乱MACQUARIE ISLAND:from Chaos to Conservation(教材P51)麦夸里岛：从紊乱到修复麦夸里岛：从紊乱到修复【常见搭配】：【常见搭配】：cause chaos 导致混乱 Heavy snow has caused total chaos on the r

7、oads.大雪导致道路上一片混乱。in chaos 处于混乱之中 The house was in chaos after the party.聚会后，房子里一片狼藉。Understanding ideasUnderstanding ideas While reading words2.appetite n.食欲，胃口食欲，胃口；强烈欲望；强烈欲望Unfortunately,the cats subsequently developed an appetite for the birds,too.(教材P50)不幸的是，这些猫随后也对鸟类产生了食欲。不幸的是，这些猫随后也对鸟类产生了食欲。【常

8、见搭配】：【常见搭配】：give sb.an appetite 使某人胃口大开 Exercise gives her a good appetite.运动使她胃口大开。loss of appetite 食欲不振 Too much anxiety can result in sleeplessness and loss of appetite.过度焦虑会引起失眠和食欲不振。have an appetite for.渴望/have no appetite for.不喜欢 He has an appetite for reading.他喜欢阅读。Understanding ideasUndersta

9、nding ideas While reading words3.multiply v.（使）繁殖（使）繁殖；成倍增加，迅速增加；乘，乘以；成倍增加，迅速增加；乘，乘以Loose on the island,they did what rabbits do bestthey multiplied rapidly and began eating the native vegetation and digging holes,which caused soil erosion.(教材P50)不受束缚的兔子做了它们最擅长的事情不受束缚的兔子做了它们最擅长的事情它们迅速繁殖，开始吃当地的植物并且挖洞

10、，它们迅速繁殖，开始吃当地的植物并且挖洞，这导致了水土流失。这导致了水土流失。【用法讲解】：【用法讲解】：vi.&vt.（使）繁殖（使）繁殖 These creatures can multiply quickly.这些生物能迅速大量繁殖。It is possible to multiply these bacteria in the laboratory.在实验室里繁殖这些细菌是可能的。Understanding ideasUnderstanding ideas While reading words3.multiply v.（使）繁殖（使）繁殖；成倍增加，迅速增加；乘，乘以；成倍增加，迅速

11、增加；乘，乘以 vi.&vt.成倍增加，迅速增加成倍增加，迅速增加 The amount of information available has multiplied.可获得的信息大大增加了。Smoking multiplies the risk of heart attacks and other health problems.吸烟大大增加了患心脏病和其他疾病的风险。vi.&vt.乘，乘以乘，乘以5乘以6等于30。Multiply 5 and 6(together)and you get 30.5 multiplied by 6 is/equals/makes 30.Understand

12、ing ideasUnderstanding ideas While reading words4.the number of 的数量的数量The exploding rabbit population provided plentiful food for the cats,meaning that the number of cats also increased.(教材P50)兔子数量的迅猛增长为猫提供了充足的食物，这意味着猫的数量也增加了。兔子数量的迅猛增长为猫提供了充足的食物，这意味着猫的数量也增加了。【用法讲解用法讲解】：】：the number of.表示表示“的数量的数量”。T

13、he number of visitors to the Great Wall has increased.去长城的游客人数增加了。Count the number of heartbeats you feel in a minute.请数一下一分钟内你感觉到的心跳次数。Understanding ideasUnderstanding ideas While reading words4.the number of 的数量的数量【辨析比较辨析比较】：】：the number of/a number of the number of：“the number of+可数名词的复数形式”意为“的数量

14、”，作主语时，谓语动词用单数形式。a number of：“a number of+可数名词的复数形式”意为“几个，一些”，作主语时，谓语动词用复数形式。number前可用small，large，great等修饰。A large number of teachers are present today,and the number of them is 300.许多教师今天都出席了，人数有300。Understanding ideasUnderstanding ideas While reading words5.reserve n.自然保护区，（动植物）保护区自然保护区，（动植物）保护区；v

15、.预订，预约（座位、席位、房间等）预订，预约（座位、席位、房间等）；保留；保留Even after Macquarie Island became an official nature reserve in the 1970s,the rabbits remained out of control.(教材P51)甚至在甚至在20世纪世纪70年代，麦夸里岛成为官方认定的自然保护区后，兔子仍然无法控制。年代，麦夸里岛成为官方认定的自然保护区后，兔子仍然无法控制。【用法讲解用法讲解】：】：n.自然保护区，（动植物）保护区自然保护区，（动植物）保护区 The park was just a 100-a

16、cre nature reserve in the beginning,but it has developed fast over the years.这个公园起初只是一个占地100英亩的自然保护区，但是这些年来它发展得很快。Understanding ideasUnderstanding ideas While reading words5.reserve n.自然保护区，（动植物）保护区自然保护区，（动植物）保护区；v.预订，预约（座位、席位、房间等）预订，预约（座位、席位、房间等）；保留；保留 v.预订，预约（座位、席位、房间等）预订，预约（座位、席位、房间等）Ive reserved

17、 a room in the name of Jones.我以琼斯的名字预订了一个房间。v.保留保留 Id prefer to reserve(my)judgement until I know all the facts.在了解全部事实之前我不想发表意见。【知识拓展】：【知识拓展】：reserve reservation n.预订，预约；保留地；保留意见 make a reservation 预订，预约 without reservation 毫无保留地Understanding ideasUnderstanding ideas While reading words6.out of con

18、trol 失去控制失去控制Even after Macquarie Island became an official nature reserve in the 1970s,the rabbits remained out of control.(教材P51)甚至在甚至在20世纪世纪70年代，麦夸里岛成为官方认定的自然保护区后，兔子仍然无法控制。年代，麦夸里岛成为官方认定的自然保护区后，兔子仍然无法控制。【用法讲解】：【用法讲解】：out of control 失去控制失去控制 The fire is burning out of control in the center of the c

19、ity.正在市中心燃烧的大火失去了控制。A truck ran out of control on the hill.一辆卡车在山上失去了控制。Understanding ideasUnderstanding ideas While reading words6.out of control 失去控制失去控制【知识拓展】：【知识拓展】：in control(of sth.)掌管（某物事），控制（某物事）in the control of.受控制 lose control of.失去对的控制 beyond ones control某人无法掌握，某人无法控制 be under control被控制

20、住，处于控制之下 bring/keep/get sth.under control 控制得住，抑制得住（从而不造成损害）Understanding ideasUnderstanding ideas While reading words7.decrease vi.&vt.（使大小、数量等）减少，减小，降低（使大小、数量等）减少，减小，降低 But although the virus caused the rabbit population to decrease from 130,000 to around 10,000,it also meant less food for the cat

21、s.(教材P51)但是虽然该病毒使得兔子的数量从但是虽然该病毒使得兔子的数量从13万只减少到万只减少到1万只左右，这也意味着猫的食物更少了。万只左右，这也意味着猫的食物更少了。【常见搭配】【常见搭配】:decrease by.减少了（表示减少的量）decrease(from.)to.（从）减少到（表示减少后的量）decrease in.在方面减少Understanding ideasUnderstanding ideas While reading words【用法讲解】：【用法讲解】：vi.&vt.（使大小、数量等）减少，减小，降低（使大小、数量等）减少，减小，降低 People plant

22、ed trees on the waste hills to decrease soil erosion.人们在荒丘上种植了树木，以减少水土流失。The number of the students in our school has decreased to 1,200.我们学校的学生数量已减少到了1200人。Compared with last year,the price of wheat has decreased by 15%this year.和去年相比，今年小麦的价格已降低了15%。7.decrease vi.&vt.（使大小、数量等）减少，减小，降低（使大小、数量等）减少，减小

23、，降低 Understanding ideasUnderstanding ideas While reading words8.up to The cats in consequence turned their attentionand their stomachsback to the native birds,killing up to 60,000 each year.(教材P51)结果这些猫把它们的注意力结果这些猫把它们的注意力以及它们的胃口以及它们的胃口转回到转回到了了当地的鸟类身上，它们每年杀死的鸟当地的鸟类身上，它们每年杀死的鸟多达多达6万只。万只。【用法讲解】：【用法讲解】：

24、到达（某数量、程度等）到达（某数量、程度等）The spokesman said the high-speed train can be up to 350 kilometers per hour.发言人说，高铁的速度可达每小时350千米。Up to one hundred thousand people are still without jobs.有多达10万人仍然没有工作。Understanding ideasUnderstanding ideas While reading words8.up to 表示表示“到到为止为止”，相当于，相当于till或或until。Lisa contin

25、ued to care for her grandma up to the time of her death.丽莎一直照顾她的祖母，直到她去世。up to now 直到现在（常与现在完成时连用）：Up to now,the writer has written six stories,three of which are about rural life.到目前为止，这位作家已经写了6个故事，其中有3个是关于乡村生活的。Understanding ideasUnderstanding ideas While reading words8.up to （体力或智力上）能胜任（体力或智力上）能胜

26、任 Im afraid Tim just isnt up to the job.恐怕蒂姆无法胜任这份工作。是（某人）的义务；由（某人）决定是（某人）的义务；由（某人）决定 Its up to the travel companies to warn customers of any possible dangers.旅游公司有义务预先告知顾客任何可能的危险。Understanding ideas【句式剖析】：【句式剖析】：否定副词nor位于句首，句子用部分倒装语序。当含有否定意义的词或短语置于句首时，句子须用部分倒装语序，即把助动词、情态动词、be动词移至主语之前。这样的词或短语有never，

27、neither，nor，not，seldom，little，hardly，rarely，scarcely，at no time，by no means，in no way等。如：Never have I seen such an amazing performance.我从未见过如此精彩的表演。In no way shall I give up.我决不放弃。1.Nor would they fail to imagine how its native inhabitants,including royal penguins,king penguins,and elephant seals,ex

28、isted in perfect harmony with their natural habitat for thousands of years.(教材P50)他们也不会想象不到，几千年来，本地栖居的动物，包括皇家企鹅、帝企鹅和海象，是如何与它们的自然栖息地完美地和谐共存的。While reading sentences While reading sentences2.The end result was that parakeets,once large in number and native to the island,died out in 1891.(教材P50)最终的结果是，

29、岛上原本数量众多的本土鸟类长尾鹦鹉，在1891年灭绝了。Understanding ideas【句式剖析】：【句式剖析】：that在此引导表语从句，说明主语的内容。只起连接作用，既不充当句子成分，本身也没有词义。The first unique human characteristic is that humans have extraordinarily large brains compared with other animals.第一个人类独有的特征是，与其他动物相比，人类有非常大的大脑。（2019江苏）The good news is that therere really only

30、 three kinds of decisions you need to make about the colour in your home.好消息是，关于你家里的颜色，你只需要作三种决定。Understanding ideas After reading the structureMACQUARIE ISLAND:from Chaos to ConservationPara.1 :the present situation of the islandPara.2-3 :the recent historythe introduction of invading speciesPara.4

31、 :the plan to remove rabbits from the islandPara.5 :While the cats away,the mice will play.Para.6 :the programme to tackle the rat,mouse and rabbit problem once and for allUnderstanding ideas After reading Read for detailed informationPara.1:the present situation of the islandthe locationthe descrip

32、tionin the South-west Pacific Ocean,halfway between Australia and AntarcticaNative inhabitants existed in perfect harmony with their natural habitat.strong windsstormy seasthe long,thin shapethe green grassthe bare rocka UNESCO World Heritage SiteUnderstanding ideas After reading Read for detailed i

33、nformationPara.2-3:the recent history the introduction of invading speciesrats and miceeating the birds eggs and attacking any baby birdscatsdeveloping an appetite for the birdsrabbitscausing soil erosion,providing plentiful food for the cats and leading to more cats hunting the birdsParakeets died

34、out in 1891.Understanding ideas After reading Read for detailed informationPara.4:the plan to remove rabbits from the islandA virus was released onto the island.Traps and dogs were used to catch the cats.Understanding ideas After reading Read for detailed informationPara.5:While the cats away,the mi

35、ce will play.The mouse and rat population started to increase.The number of rabbits exploded once again.Their digging caused some land to collapse,and killed a substantial number of penguins.Understanding ideas After reading Read for detailed informationPara.6:the programme to tackle the rat,mouse a

36、nd rabbit problem once and for alldropping poison from helicoptersremoving the last remaining invading speciesPostscriptThe islands ecology is finally on the road to recovery.After readingUnderstanding ideas3.Choose the authors purpose in writing the passage and give your reasons.1)To analyse how Ma

37、cquarie Island was saved from destruction.2)To inform readers of the chaos caused on Macquarie Island by humans.3)To entertain readers with a funny story about what happened on Macquarie Island.4)To suggest ways in which an ecosystem can be protected.From the title,we know the Island was saved from

38、destruction(from chaos)to conservation.After readingUnderstanding ideas4.Organise information from the passage and complete the flow chart.Humans arrived on Macquarie Island.To live there.Rats and mice were brought there by accident,and _ _.To control the rats and mice.ate the birds eggs and attacke

39、d baby birdsCats were brought to the island.Cats ate the birds too.After readingUnderstanding ideas4.Organise information from the passage and complete the flow chart.Rabbits multiplied and caused soil erosion,and _ _.provided plentiful food for the cats.Rabbits were introduced to the island.The rab

40、bit population decreased.As a source of food for humans.A virus was released onto the island.To remove all the rabbits from the island.After readingUnderstanding ideas4.Organise information from the passage and complete the flow chart.The mouse and rat population started to increase.Traps and dogs w

41、ere used.To catch the cats.The islands ecology is on the road to recovery.Poison was dropped from helicopters.To solve the rat,mouse and rabbit problem.After readingUnderstanding ideasThink&Share1 What is your understanding of“.we humans owe it to the island to give it a happy ending”?The destructio

42、n of the islands ecosystem was caused by animals that humans had accidentally brought with them.Human intervention has further undermined the islands ecological balance.So man should make an attempt to restore the islands natural balance.Now talk about how human interference led to such severe conse

43、quences for Macquarie Island.After readingUnderstanding ideasThink&Share2 Do you think it was right to eradicate the“pests”from Macquarie Island?Give your reasons.3 How could similar situations be avoided in the future?4 What language can you use to talk about cause and effect?How would you apply it to your reading and writing?Now talk about how human interference led to such severe consequences for Macquarie Island.