04(选必1)UNIT3CONSERVATIONSectionⅠTOPICTALK&LESSON（导学案4）

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UNIT 3 CONSERVATION






1．Only to obey nature in order to overcome nature.
                —Charles Darwin
要征服自然就只能遵从自然。        
                ——查尔斯·达尔文
2．Nature is kind of a loving mother，but also a butcher in cold blood.
                —Victor Hugo
自然不仅是位慈爱的母亲，还是个冷血的屠夫。
                ——维克多·雨果
3．It is usually their own surroundings as a form of free merchandise，I do not know any way to cherish and spoil.                 —Gan Harman
我们常把环境看作免费商品而不知珍惜。        ——甘·哈曼
4．The land to all the people are the essence of the material，and finally，it has been there from the people of the rebate is rubbish these substances.
        —Walt Whitman
土地对人类来说是根本，然而人类给予自然的是垃圾。
                ——沃尔特·惠特曼
5．For years we've been conquering nature.Now we're beating it to death.
                —Tom McMillan
我们花了多年时间来征服自然，而如今又开始把它往死里推。
                ——汤姆·麦克米兰


Harmony with the environment is that we live in on Earth，who is a natural son，and not only to natural persons as the conqueror，as we all know，there is only one earth and the mountains on Earth，the animals.Plant human cells，if it damaged，destroyed nature organizations，to the eradication of mankind.Therefore，the environment must be linked with social ethics，character education and practice acts as an important element of it.Everyone must fulfil its responsibilities and obligations to protect the environment.



The first Earth Day was in 1970.People were beginning to worry about what we were doing to our environment.So they set up Earth Day to tell everyone about their worries.
In 2007 organizers over 150 countries planned over 4，000 big events.But Earth Day is not just about marches(游行) and big events.In the week around Earth Day (22 April) there were many thousands of smaller，local events.These events dealt with environmental problems in the neighborhood.The World Wide Fund for Nature made a list of 5 things that each person could do to save the environment.
*Don't leave the tap running.
*Turn off lights when you leave a room.
*Turn off your computer every night.
*Wash your clothes，and yourself，in warm or cold water，not hot water.
*Dishwashers use as little water as possible.If we all do at least 2 of these all the time，we can make a big difference.
[探究发现]
1．What is the purpose of people to set up Earth Day?
To tell everyone about their worries.
2．What should people do when the water keeps running from a tap?
People should stop it from running/Stop it from running.
3．Besides the five，what else can you do to save our environment?
We shouldn't throw rubbish everywhere...
Section Ⅰ　TOPIC TALK & LESSON 1




Ⅰ.匹配词义
A．单词匹配
(　　)1.conservation        A．adj.塑料制的
(　　)2.plastic        B．n.one thing on a list of things to
        buy，do，talk about，etc.
(　　)3.item          C．n.protection
(　　)4.unrecyclable        D．adv.非法地，违法地
(　　)5.illegally          E．adj.有教育意义的；知识性强的
(　　)6.informative          F．adj.不可回收的
(　　)7.extinct          G．n.物种，种
(　　)8.species         H．adj.no longer in existence
(　　)9.endangered          I．adj.太阳光(能)的
(　　)10.solar          J．adj.濒危的
[答案]　1—5　CABFD　6—10　EHGJI
B．短语匹配
(　　)1.have a role          A．彻底毁灭
(　　)2.do one's part        B．起某种作用
(　　)3.wipe out          C．尽自己的职责
(　　)4.be to blame        D．消失；绝迹，灭绝
(　　)5.be at risk          E．把……归咎于
(　　)6.die out          F．处境危险，受到威胁
[答案]　1—6　BCAEFD
Ⅱ.默写单词
1．threat n．　　　        威胁；(灾难等坏事)发生的可能
2．hunt vi.& vt.          猎取，猎杀
3．incredibly adv.          非常地，极端地
4．unusual adj.          异常的；不平常的
5．mass adj.          大量的
6．varied adj.          各种各样的，形形色色的
7．decrease vi.& vt.          减少
n.          减少；减少的量
8．blame vt.          责怪，指责
9．hatch vi.& vt.          (使)孵化
10．restore vt.          (使)恢复


Ⅰ.语境填词
hunted；mass；affected；informative；destroyed；restore；species；switch；decreased；solar
1．No one was injured in the explosion，but the building was completely destroyed．
2．Every time I switch on the TV，there's football.It's overkill.
3．Whales are still being hunted and killed in the Arctic.
4．Many species have been shot to the verge of extinction.
5．The government ordered the police out to restore order and peace in the streets.
6．China is the world's top investor in wind and solar power.
7．The south of the country was worst affected by the drought.
8．The number of new students decreased from 210 to 160 this year.
9．The UK，uniquely，has not had to face the problem of mass unemployment.
10．I truly hope you found this writing enjoyable and informative．
Ⅱ.语法填空之派生词
1．She is interested in conservation(conserve)．
2．Can we stop using the unrecyclable(recycle) style of lunch boxes?
3．Up to two thirds of 14­16 year olds admit to buying drink illegally(legal)．
4．It's a good restaurant，and incredibly(incredible) cheap.
5．The book is extremely informative(information) about life in Roman times.
6．He had had a varied(vary) training and held many offices.
7．It was an unusual(usual) day for summer，damp and chilly.
8．14 percent of primate species are highly endangered(endanger)．
9．He said army officers had threatened(threat) to destroy the town.
10．An operation is beginning to try to save a species of crocodile from extinction(extinct)．


1．Extinctions, where entire species are wiped out, are not unusual in our Earth's history.
物种灭绝，即某个物种的完全消失，在地球的历史上并不罕见。
2．Although it is not unusual for species to die out naturally，the rate at which this is now happening is cause for concern.
虽然物种的自然灭绝并不罕见，但现在灭绝的速度让人担忧。
3．It is clear that human activity has negatively affected all other species on Earth, including animals and plants.
很明显，人类活动已经对地球上所有其他物种产生了负面影响，包括动物和植物。
4．Without forests, we would have no air to breathe，and  without clean water we would be unable to survive.
没有森林，我们就没有可以呼吸的空气，没有干净的水，我们就无法生存。
5．To help them survive, people are restoring their habitats and removing small animals that hunt them，such as mice and cats from the islands where they live.
为了帮助它们生存，人们正在恢复它们的栖息地，并将捕食它们的小动物，如老鼠和猫，从它们生活的岛屿上赶走。


词语助读
①entire species整个物种
②wipe out彻底毁灭
③unusual adj.异常的；不平常的
④in fact事实上
⑤the third mass extinction第三次生物大灭绝
⑥known as以……而著称
⑦varied adj.各种各样的，形形色色的
⑧according to根据
⑨volcanic eruptions火山爆发
⑩asteroid n．小行星
⑪the decrease of the oxygen content含氧量下降
⑫global warming全球变暖
⑬be to blame把……归咎于
⑭die out 消失；绝迹，灭绝
⑮cause for concern令人担心的原因
⑯due to natural causes由于自然原因
⑰that is即
⑱human activity人类活动
⑲a long list of reasons很多原因
⑳factory farming工业化种植
other species对所有其他物种都有负面影响
species拯救濒危物种
原文呈现
THE SIXTH EXTINCTION
Extinctions，where entire species① are wiped out②(1)，are not unusual③ in our Earth's history.In fact④，over 90 percent of all species that ever lived(2) are now extinct.In the last 500 million years，there have been five times when life on Earth has almost ended(3)．These include the third mass extinction⑤，known as⑥ the “Great Dying”，which killed 90% to 96% of all species(4)．And the fifth event，which occurred 66 million years ago(5)，caused the death of the dinosaurs.The reasons for extinctions are varied⑦.According to⑧ scientists，they include volcanic eruptions⑨，asteroids⑩ hitting the Earth from space，changes in sea levels，the decrease of the oxygen content⑪of the sea and global warming⑫.Many scientists say we are now entering the Earth's sixth mass extinction(6)．This time，human activity will be to blame⑬.
(1)where引导非限制性定语从句，修饰先行词Extinctions。
(2)that引导限制性定语从句，修饰先行词species。
(3)when引导限制性定语从句，修饰先行词five times。
(4)which引导非限制性定语从句，修饰先行词the third mass extinction。
(5) which引导非限制性定语从句，修饰先行词the fifth event。
(6)该句为省略that的宾语从句。
(7) 句中although引导让步状语从句，at which...happening为限制性定语从句，修饰先行词rate。
(8)句中who...the US为限制性定语从句，修饰先行词scientists，how...natural causes为宾语从句。
(9)that引导宾语从句。
(10)why引导限制性定语从句，修饰先行词reasons。
(11)it为形式主语，真正的主语为后面的that从句。
(12)句中if引导条件状语从句，who...the issue为限制性定语从句，修饰先行词scientists，that...die out为宾语从句。
(13)as引导原因状语从句。
(14)句中that引导宾语从句，if we take action now为条件状语从句。
(15)省略that的宾语从句，其中we live为限制性定语从句，修饰先行词the way。
(16)where引导定语从句，修饰先行词special areas。
(17)how引导宾语从句。
(18)句中if引导条件状语从句，that we live on为限制性定语从句，修饰先行词planet。
The Black Robin
(19)that引导限制性定语从句，修饰先行词the birds。
(20)句中that hunt them为限制性定语从句，修饰先行词small animals；where they live也是限制性定语从句，修饰先行词the islands。
译文参考
第六次生物大灭绝
物种灭绝，即某个物种的完全消失，在地球的历史上并不罕见。事实上，超过90%的物种已经灭绝。在过去的5亿年里，地球上的生命有5次几乎灭绝。其中包括第三次生物大灭绝，即所谓的“大灭绝”，导致90%到96%的物种灭绝。发生在6 600万年前的第五次灭绝事件导致了恐龙的灭亡。灭绝的原因多种多样。科学家们认为，造成物种灭绝的原因包括火山喷发、小行星从太空撞击地球、海平面高度改变、海水中含氧量下降和全球变暖等。许多科学家说，我们现在正在进入地球的第六次大灭绝。这一次，人类活动将是罪魁祸首。
虽然物种的自然灭绝并不罕见，但现在灭绝的速度让人担忧。美国布朗大学和杜克大学的科学家们于2015年进行了一项研究，考察了自然原因导致物种灭绝的速度，即“背景灭绝率”。他们发现，人类活动导致物种灭绝的速度是正常情况下的1 000倍。有很多为什么如此多的物种灭绝的原因：空气和水污染，森林被破坏，工业化种植和过度捕捞。很明显，人类活动已经对地球上所有其他物种产生了负面影响，包括动物和植物。
如果第六次大灭绝发生，研究这个问题的科学家们认为，地球上多达四分之三的物种可能会灭绝。当然，由于我们人类依靠如此多的物种生存，我们也将面临灭绝的风险。我们的世界和我们的生活依赖于动物和植物之间的平衡。没有森林，我们就没有可以呼吸的空气，没有干净的水，我们就无法生存。
第六次物种灭绝可以避免吗？专家们说，如果我们现在就采取行动，还为时不晚。这意味着我们必须显著地改变我们的生活方式。例如，我们需要采取措施拯救濒危物种，包括建立特别保护区，在这里动植物可以得到保护。我们需要通过使用更清洁、更自然的能源来改变工作和旅行的方式，如风能和太阳能。我们还需要改进我们的耕作方法，以减少对水、空气和土地的污染。简而言之，如果我们想要生存，我们需要停止破坏我们赖以生存的星球，并开始保护它。
黑知更鸟
黑知更鸟是人类从灭绝中拯救出来的鸟类。1980年，世界上只剩下5只黑知更鸟。它们都生活在离新西兰海岸不远的一个小岛上。其中只有一只名叫“老布鲁”的雌鸟能下蛋。野生动物工作者开始了饲养黑知更鸟的计划。他们保护老布鲁的蛋，帮助它们孵化并照顾小鸟。由于他们的努力，现在有了250多只黑知更鸟，而且数量还在增加。为了帮助它们生存，人们正在恢复它们的栖息地，并将捕食它们的小动物，如老鼠和猫，从它们生活的岛屿上赶走。




速读课文，完成下列任务
Ⅰ.阅读判断
判断以下句子提供的信息是正确，还是错误，还是没有提及：
1．Over 90% of all species that ever lived on the earth are now extinct.
A．Right.　        B．Wrong.　　        C．Not mentioned.
2．There were about six extinctions in the past.
A．Right.        B．Wrong.          C．Not mentioned.
3．It is because of human activities that species are dying out faster than before.
A．Right.        B．Wrong.          C．Not mentioned.
4．Experts say that it is too late to prevent the sixth extinction.
A．Right.        B．Wrong.          C．Not mentioned.
5．Black robins are likely to disappear on the earth in the next century.
A．Right.        B．Wrong.          C．Not mentioned.
[答案]　1—5　ABABC
Ⅱ.补全信息
选择正确选项填入空白处，补全所给句子提供的信息：
A．which occurred 66 million years ago
B．when life on Earth has almost ended
C．where entire species are wiped out
D．where plants and animals can be protected
E．at which this is now happening
F．who have studied the issue
1．Extinctions，，are not unusual in our Earth's history.
2．In the last 500 million years，there have been five times．
3．And the fifth event，，caused the death of the dinosaurs.
4．Although it is not unusual for species to die out naturally，the rate
is cause for concern.
5．If a sixth mass extinction occurs，scientistsbelieve that up to three quarters of all species on Earth could die out.
6．For example，we need to take steps to save endangered species，including setting up special areas．
[答案]　1—6　CBAEFD
Ⅲ.表格填空

The meaning of extinction	Entire species are 1.wiped out.
Extinctions and their consequences	There have been 2.five times when life on Earth has almost ended. The third mass extinction killed 90% to 96% of all species. The fifth mass extinction caused the death of the 3.dinosaurs． If a sixth mass extinction occurs，up to three quarters of all species on Earth could 4.die out.
Main reasons for extinctions	Volcanic eruptions. Asteroids hitting the Earth from space. Changes in 5.sea levels． The 6.decrease of the oxygen content of the sea. Global warming. Human 7.activity.
Steps to avoid the sixth mass extinction	Save 8.endangered species. Change how we work and travel. Improve our 9.farming methods． Stop 10.destroying the planet that we live on and start to protect it.

细读课文，完成下列任务
Ⅰ.主旨匹配

段落	主旨大意
1.Para.1	A.The effect of human activity on species.
2.Para.2	B.The consequences of the sixth extinction.
3.Para.3	C.How to avoid a sixth extinction.
4.Para.4	D.The mass extinctions in the history.

[答案]　1—4　DABC
Ⅱ.课文理解
1．When did dinosaurs die out according to the passage?
A．More than 500 million years ago.
B．More than 66 million years ago.
C．In the third mass extinction.
D．In the fourth mass extinction.
2．Which of the following is one of unnatural reasons for extinctions?
A．Volcanic eruptions.
B．Asteroids hitting the Earth.
C．Changes in sea levels.
D．Air and water pollution.
3．What has made the species on Earth die out at a higher rate?
A．Natural causes.
B．Global warming.
C．Human activity.
D．No clean water.
4．Why do we need to change the way we live now?
A．To avoid a sixth extinction.
B．To live with others in peace.
C．To save natural sources of energy.
D．To work better and travel faster.
[答案]　1—4　BDCA
Ⅲ.概要写作微技能
概要写作微技能——找出文中各个段落的主题句并进行高度概括
1．Para.1：In the last 500 million years，there have been five times when life on Earth has almost ended.
→高度概括为：There have been five mass extinctions in the history.
2．Para.2：They found that human activity is causing species to die out 1，000 times faster than normal.
→高度概括为：It is human activity that is causing species to die out much faster.
3．Para.3：Of course，as we humans depend on so many species for our survival，we would also be at risk of dying out.
→高度概括为：Man is also at risk of dying out.
4．Para.4：Can a sixth extinction be avoided？Experts say that it is not yet too late，if we take action now.
→高度概括为：The sixth extinction can be avoided if we take action now.




1．conserve v．保存；保护；储藏→conservation n．保护→conservative adj.保守的；守旧的
2．recycle vi.& vt.再利用，回收利用→recyclable adj.可回收的→unrecyclable adj.不可回收的
3．threat n．威胁；(灾难等坏事)发生的可能→threaten v．威胁；恐吓；危及→threatened adj.受到威胁的
4．inform vt.通知；告知→information n．信息→informative adj.有教育意义的；知识性强的
5．legal adj.合法的→legally adv.合法地→illegally adv.非法地，违法地
6．extinct adj.灭绝的，绝种的→extinction n．灭绝；绝种；消亡
7．incredible adj.极好的；难以置信的→incredibly adv.非常地，极端地
8．urge v．督促；敦促；力劝→urgent adj.紧急的，急迫的→urgency n．紧迫；急迫
9．usual adj.经常的，通常的；寻常的，惯常的→unusual adj.异常的；不平常的
10．vary v．变化→varied adj.各种各样的，形形色色的→variety n．变化；品种；种类
11．endanger vt.危及，使遭受危险→endangered adj.濒危的


1．decrease vi.& vt.减少n．减少；减少的量
①The population began to decrease.        vi.减少
②They decreased the size of the group from 25 to 15.        vt.减少
③The decrease in sales was almost 20 percent.        n.减少；减少的量
2．affect v．影响；侵袭；使感染；(感情上)深深打动
①Your opinion will not affect my decision.        影响
②They were deeply affected by the news of her death.        深深打动
③Arthritis is a crippling disease which affects people all over the world.
                使感染


Words and Phrases
(教材P108～109)We definitely need to switch to different forms of power as soon as possible.
我们当然需要尽快转到不同形式的能量。
[例]　The remote control allows you to switch easily between TV channels.
遥控器让你在不同电视频道之间轻松地转换。
[知识拓展]
switch off 　　        切断(电源、气体等)
switch on           打开(开关)；接通(电源等)
switch (from...) to...           (从……)转变成，(从……)转换到
switch sth.with sb.          和某人交换某物
switch over          转换；换台，换频道
[即学即练]——单句语法填空
①Switch off the TV before you go out.
②She switched on the lamp because it was dark.
③We asked them if they would switch places with us.
[小片段填空]
Lucy returned home from work early.After changing clothes，she switched off the light and came downstairs.Then she switched on the TV and switched over with boredom.
露西早早下班回到家。换完衣服后，她关掉灯来到楼下。然后打开电视机，无聊地换着频道。
(教材P109) That's an incredibly urgent matter...
这是一件非常紧急的事……
[例]　He asked to see the manager for something urgent.
他有急事求见经理。
[知识拓展]
(1)urge v．　　　        催促；力劝；强烈要求
urge sb.to do sth.          敦促某人做某事
urge that sb.(should) do...         敦促某人做某事
urge sth.on sb.          向某人提出/力陈某事
(2)urgency n.          紧急的事
[即学即练]——单句语法填空
①The report urged that all children (should) be taught(teach) to swim.
②He denounces people who urge him to change(change) his ways.
③I need not press on you the urgency(urgent) of the matter.
[小片段填空]
Mr Zhang urged that his daughter (should) study abroad(极力主张女儿出国留学)．Whenever he talked to her on the phone，he would urge her to make preparations(督促她做准备)．To his great joy，his daughter went to study in Britain at last.
(教材P52) How many times up to today has life on Earth almost died out?
到今天为止，有多少次地球上的生命几乎灭绝？
[例]　As a result these endangered animals may even die out.结果，这些濒危动物甚至会灭绝。
[知识拓展]
die away 　        逐渐减弱，逐渐模糊，逐渐消失
die down          逐渐降低，逐渐平息
die off           相继死去
die of           死于(内因)
die from           死于(外因)
[即学即练]——单句语法填空
①As the region is becoming hotter，this kind of grass is dying off．
②Their chatter and laughter die away as the group rushed out of the classroom.
③When all the guests had left，the whole house died down．
④We need to take action before all the endangered animals died out．
(教材P52)Extinctions，where entire species are wiped out，are not unusual in our Earth's history.物种灭绝，即某个物种的完全消失，在地球的历史上并不罕见。
[例]　The plague once could wipe out a village.
鼠疫曾一度可以夺走整个村庄村民的生命。
[知识拓展]
wipe away　　　        擦去，消除
wipe off          擦掉，除掉
wipe up          擦净，打败，消灭
wipe sth.from/off sth.          从……上擦去某物
wipe...with...          用……擦……
[即学即练]——单句语法填空
①When you've finished with it，simply wipe it clean with a damp cloth.
②He wiped the marks off the wall.
(教材P52) The reasons for extinctions are varied.
灭绝的原因多种多样。
[例]　It is essential that your diet is varied and balanced.关键是你的饮食要多样化，并保持均衡。
[知识拓展]
(1)various adj.　　        各种各样的
various views          各种各样的观点
for various reasons          因种种理由
(2)variety n.          种种；种类；多样化
a variety of/varieties of          多种多样的
(3)vary v.          变化，不同
vary with...          随……而变化
vary from...to...          从……到……变化不等
[即学即练]——单句语法填空
①They were late for the meeting for a variety(vary) of reasons.
②There are various(vary) plants and flowers in the park.
③The weather here varies(vary) with seasons.
[小片段填空]
The result showed that for a same cotton，its various growing stages and whole growing period vary in different year with different temperature.There are also a variety of reasons that affect its growth.
(教材P52) According to scientists，they include volcanic eruptions，asteroids hitting the Earth from space，changes in sea levels，the decrease of the oxygen content of the sea and global warming.
科学家们认为，造成物种灭绝的原因包括火山喷发、小行星从太空撞击地球、海平面高度改变、海水中含氧量下降和全球变暖等。
[例]　If their habitat is threatened or they cannot find enough food，their numbers may decrease.
如果它们的栖息地受到威胁或者它们找不到足够的食物，它们的数量就会减少。
[知识拓展]
(1)on the decrease 　　        在减少中
a decrease in...          在……方面减少
(2)decrease to...          减少到……
decrease by...          减少了……
decrease from...to...          从……减少到……
[即学即练]——单句语法填空
①There is a decrease of nearly 7% in the number of visitors to the museum.
②The number of independent firms decreased from 198 to 96.
③Because of human activity，the number of some rare animals is on the decrease.
[名师点津]
decrease的反义词increase的用法
increase to 增加(长)到……
increase by 增加(长)了……
on the increase 在增加中
(教材P52) This time，human activity will be to blame.
这一次，人类活动将是罪魁祸首。
[例]　It seemed that the water was to blame.
看来水是罪魁祸首。
[知识拓展]
(1)be to blame　　　        把……归咎于
be to blame for sth.          对某事负有责任，应受责备
blame sb.for sth.          因某事责备某人；把某事归咎于某人
blame sth.on sb./sth.          把某事归咎于某人/某事
(2)put/lay the blame for sth.on sb.
          将某事归咎于某人
get/accept/bear/take the blame for sth.
          对某事承担责任
[即学即练]——单句语法填空
①If that happens，the coach will take the blame for it.
②You are not to blame (blame)．I can't put the blame on you.
③You shouldn't blame John for the failure.
＝You shouldn't blame the failure on John.
[小片段填空]
They all blamed the car accident on him.In fact，he was really to blame for his careless driving.So he got the blame for it without any complaint.
他们把车祸归咎于他。实际上，他确实应该因粗心驾驶受到责备。于是，他毫无怨言地担负起了车祸的责任。
(教材P53) It is clear that human activity has negatively affected all other species on Earth，including animals and plants.很明显，人类活动已经对地球上所有其他物种产生了负面影响，包括动物和植物。
[例]　I had to make important decision that would affect me for the rest of my life.
我不得不作出将影响我后半生的重大决定。
[知识拓展]
(1)affect sb./sth.　        影响某人某物
(2)effect n.          结果；效力；影响；效果；作用
put/bring...into effect          使生效，实行
in effect          事实上；实际上
take effect          生效；奏效
come into effect          开始实施；开始生效
have an effect on          影响……
[即学即练]——单句语法填空/一句多译
①In effect，we feel superior to them.
②The new law is said to have come into effect from April.
③Great scientific achievements will greatly affect our life as well as society.
＝Great scientific achievements will have a great effect on our life as well as society.
重大的科技成果将对我们的生活和社会产生很大的影响。
(教材P53) Of course，as we humans depend on so many species for our survival，we would also be at risk of dying out.
当然，由于我们人类依靠如此多的物种生存，我们也将面临灭绝的风险。
[例]　As with all diseases，certain groups will be more at risk than others.
所有的疾病都是如此，一些人比另一些人更容易受到威胁。
[知识拓展]
(1)be at risk of　　        处于……危险之中
at all risks＝at any risk          无论冒什么风险
at the risk of...         冒……的危险
take risks/a risk          冒险
take/run the risk of doing sth.         冒险做某事；冒做某事的危险/风险
put one's life at risk          冒生命危险
(2)risk doing sth.          冒险做某事
risk one's life to do sth.          冒着生命危险做某事
[即学即练]——单句语法填空
①He jumped into the river at the risk of losing his life.
②I didn't want to take/run the risk of leaving (leave) John alone.　
③He worked hard，for he couldn't risk losing (lose) the good job.＝ He worked hard，for he couldn't take/run the risk of losing the good job.
Sentence Pattern
(教材P53) It is clear that human activity has negatively affected all other species on Earth，including animals and plants.
很明显，人类活动已经对地球上所有其他物种产生了负面影响，包括动物和植物。
句式分析：句中it是形式主语，真正的主语是后面的that从句。
[例1]　It is certain that free medical care will be given to most people in our city.
可以确定的是我们城市的多数人将享受免费医疗。
[例2]　It was obvious that the driver could not control his car.
显然这位司机无法控制他的汽车了。
[知识拓展]
it 作形式主语，真正的主语为that引导的从句的常见形式有：
(1)It be＋形容词(obvious，possible，strange，natural，important...) ＋that 从句。
(2)It be＋名词短语(a pity，a fact，a wonder，a shame，an honour，no wonder...) ＋that 从句。
(3)It be＋过去分词(said，thought，hoped，believed，declared，supposed，reported...) ＋that 从句。
(4)It＋不及物动词(seem，occur，happen...) ＋that 从句。
[即学即练]——完成句子
①It is obvious that nobody will like to have dinner in such a dirty place.
很明显，没有人想在这么脏的地方吃饭。
②It's a shame that we failed to fulfil the task ahead of time.
我们没能提前完成任务，真感到惭愧。
③It is believed that it is the earliest and largest paper­making workshop site ever found in ancient China.
人们认为这是迄今为止在中国发现的最早的也是最大的造纸作坊。
④It occurred to me that I had left my ticket at home.
我突然想起把票忘在家里了。


1．Although it is not unusual for species to die out naturally，the rate at which this is now happening is cause for concern.
[分析]　句中Although it is not unusual for species to die out naturally为although引导的让步状语从句，at which this is now happening为限制性定语从句，修饰先行词rate。
[翻译]　虽然物种的自然灭绝并不罕见，但现在灭绝的速度让人担忧。
2．If a sixth mass extinction occurs，scientists who have studied the issue believe that up to three quarters of all species on Earth could die out.
[分析]　句中If a sixth mass extinction occurs 为if引导的条件状语从句，who have studied the issue为who引导的限制性定语从句，修饰先行词scientists，名词性从句that up to three quarters of all species on Earth could die out作动词believe的宾语。
[翻译]　如果第六次大灭绝发生，研究这个问题的科学家们认为，地球上多达四分之三的物种可能会灭绝。

教材	高考
1.We definitely need to switch to different forms of power as soon as possible.	(2020·天津卷)And the officer can't let him get away.He pulls out a special device，points it at the suspect，and switches it on.
2.How many times up to today has life on Earth almost died out？	(2020·北京卷)The Neanderthals lived alongside human ancestors in Europe for tens of thousands of years，before dying out about 40，000 years ago.
3.According to scientists，they include volcanic eruptions，asteroids hitting the Earth from space，changes in sea levels，the decrease of the oxygen content of the sea and global warming.	(2020·北京卷)Negative self­talk damages self­confidence and decreases self­respect.
4.It is clear that human activity has negatively affected all other species on Earth，including animals and plants.	(2020·江苏卷)Athletes and scientists have long known that meal timing affects performance.

Ⅰ.单句语法填空
1．It was surprising that she passed the difficult exam.
2．At the risk of being blamed(blame)，he drove his father's car to school.
3．Oil spills are having a devastating effect on coral reefs in the ocean.
4．The number of teaching staff members in this school has decreased to 700 persons.
5．Tom's life was varied(vary) and pleasant enough，on the whole.
6．The tsunami that followed engulfed the northeast and wiped out entire towns.
7．Many of our old customs are dying(die) out day by day.
8．We need to switch off the cell­phone and leave the children to play by themselves.
9．The country needs new leadership if she is to play a role in future development.
10．The society was set up to preserve endangered(endanger) species from extinction.
Ⅱ.短语填空
have a role；do one's part；die out；wipe out；be to blame；be at risk
1．Every student ought to do his part to make steady progress.
2．At one stage it looked as if it might not have a role at all.
3．Only in this way can we wipe out the enemy troops.
4．Alone in his room，he asked himself whether he was to blame for the accident.
5．There are new uses of words coming in and old uses dying out．
6．123，000 people were at risk of early death over the next 20 years，the study said.
Ⅲ.课文语法填空
In our Earth's history，there have been five times 1.when life on Earth has almost ended.The third mass extinction 2.killed(kill) 90% to 96% of all species and the fifth event caused the 3.death(die) of the dinosaurs.The natural reasons include volcanic eruptions，asteroids hitting the Earth from space，changes in sea levels，the decrease 4.of the oxygen content of the sea 5.and global warming.This time，man will be 6.to blame(blame) for the Earth's sixth mass extinction.Air and water pollution，forests being destroyed，factory farming and overfishing are causing species to die out 1，000 times 7.faster(fast) than normal.We ought to take action to avoid a 8.sixth(six) extinction now，which means we have to save 9.endangered(endanger) species，change how we work and travel and improve our farming methods to reduce water，air and land pollution.In short，if we want to survive，we need to stop 10.destroying(destroy) the planet that we live on and start to protect it.


限制性定语从句和非限制性定语从句


[观察例句]
1．Eric set sail once again，this time with 25 ships，of which only 14 made it to Greenland.
2．Eric reached Greenland and discovered that people could live in the place where he landed.
3．Biarni was the man with whom Leif discussed his plans.
4．By around 900AD，there were many places in Northern Europe where the Vikings chose to live.
[归纳用法]
一、限制性定语从句与非限制性定语从句概述
1．限制性定语从句是先行词不可缺少的一部分，若去掉，主句的内容就不完整，意义也会发生改变。从句和先行词的关系十分密切，从句紧跟先行词，两者之间不可用逗号隔开。
She has found the necklace (that) she lost two weeks ago.
她找到了那条两周前丢失的项链。
2．非限制性定语从句是先行词的一个补充说明。没有它，主句也能独立存在；非限制性定语从句和先行词的关系不是很密切，两者之间用逗号隔开。
He has two sisters，who are working in the city.
他有两个姐姐，她们在城里工作。
[即学即练]——单句语法填空
①The weather turned out to be very good，which was more than we could expect.
②Is this the museum where the exhibition was held?
二、限制性定语从句和非限制性定语从句的区别
1．标点的运用有所不同
限制性定语从句一般紧跟在先行词后，其后不可用逗号分开；而非限制性定语从句也常放在先行词后，但必须用逗号与主句分开。
Who is the girl that is standing under the tree?
站在树下的那个女孩是谁？
He is a teacher of much knowledge，from whom much can be learned.
他是一个学识渊博的老师，从他那儿可以学到许多东西。
2．从句的作用不同
限制性定语从句对先行词起到修饰限制的作用，是先行词在意义上不可缺少的定语，一旦省略，主句的意思就不完整。而非限制性定语从句则是对一个概念清楚的先行词进行附加说明，若将其去掉，主句的意思仍然完整。
The next day，my brother and I went to the beach where we watched some people play volleyball.
第二天，我和弟弟去了海边。在那里，我们看到一些人在打沙滩排球。
Alice received a letter from her former classmate，which came as a surprise.
艾丽斯收到了她以前同学的一封信，这真是件令人惊奇的事情。
3．关系词的选用不同
限制性定语从句可以用关系代词who，whom，whose，that，which，关系副词when，where，why等引导，而非限制性定语从句不可用that或why来引导(上述引导词除了这两者以外均可用来引导非限制性定语从句)。
Yesterday he bought a new car，which was made in Japan.
(which不可换用that)昨天他买了一辆新车，是日本生产的。
He didn't give the reason，which explained his absence from the meeting held last week.
(which不可换用why，因为which在定语从句中作主语，而why只能在定语从句中作状语。此句也可以这样表达，He didn't give the reason，for which he was absent from the meeting held last week.)
4．从句所修饰的先行词有所不同
限制性定语从句的先行词通常是名词、代词或词组；而非限制性定语从句的先行词除了名词、代词外，还可以是句子。
This is the best book that I have ever read.
这是我曾经读过的书中的最好的一本。
He won the first prize in the contest，which was more than we expected.
他在比赛中得了一等奖，这一点真出乎我们预料。
5．关系词的省略不同
在限制性定语从句中，当关系代词在定语从句中作宾语或表语时，在口语中可以省略，关系副词有时也可省略。而非限制性定语从句中的关系代词或关系副词不可省略。
I still remember the days we spent together in college.
我仍然记得我们在大学时一起度过的日子。(we前省略了that/which)
She is not the one(that) she used to be.
她已不再是昔日的她了。(that在定语从句中作表语)
6．英译汉时有所不同
译成汉语时，往往把限制性定语从句的内容置于先行词之前；而非限制性定语从句和主句往往翻译成两个分句。
Which is the machine that we used last Sunday?
上星期天我们用的那台机器是哪一台？
The concert，which was held last week，was a great success.
那场音乐会是上周举行的，获得了巨大的成功。
He may be late，in which case we ought to wait for him.
他可能迟到，要是那样的话我们就等等他。
[即学即练] ——单句语法填空
③Liquid water changes to vapor，which is called evaporation.
④Charles Smith，who was my former teacher，retired last year.
⑤This is the house where I lived two years ago.
三、as和which引导非限制性定语从句的区别

	which	as
位置上	只能放在先行词的后面	位置灵活，可位于句前、句中，也可置于句后
搭配上	无动词的限制	谓语动词通常是表示感觉或心理活动的动词，如see，hear，know，expect，remember，guess，hope等
句意上	意为“这一点”	表示“正如……，正像……的那样”

The air quality in the city，as is shown in the report，has improved over the past two months.
正如报告所显示的，在过去的两个月里，这个城市的空气质量已有所改善。
After graduating from college，I took some time off to go travelling，which turned out to be a wise decision.
大学毕业后我抽出一部分时间去旅游，事实证明这是一个明智的选择。
[即学即练]——单句语法填空
⑥Metals have many good properties，as has been stated before.
⑦Light travels in straight lines，which explains why shadows are formed when it goes past an object.


Ⅰ.单句语法填空
1．The reason which/that he explained for his being late was that his alarm clock didn't work.
2．Life is like a long race where we compete with others to go beyond ourselves.
3．I often have the case where I can't recognise my friend's voice on the phone.
4．Some pictures of the river brought the days back to the old when they swam in it.
5．Many countries are now setting up national parks where animals and plants can be protected.
6．Mexico City，which has a population of over 10 million，is probably the fastest growing city in the world.
7．We will be shown around the city: schools，museums，and some other places，where other visitors seldom go.
8．As is known to everybody，the moon travels round the earth once every month.
9．English is a language shared by several diverse cultures，each of which uses it differently.
10．I wish to thank Professor Smith，without whose help I would never have got this far.
Ⅱ.短文语法填空
I have a good friend 1.whose name is Wang Fang.She is from a town 2.where rice is grown.She likes reading novels 3.which are written by Americans.She often goes to the park 4.where many beautiful flowers are grown.She often discusses the problems 5.that she can't solve by herself.
She went to the city 6.where her father 7.worked(work) last year to experience life.This year she wants to visit the city of Beijing 8.where her aunt lives.She is so kind 9.that she is ready to help the people 10.who are in trouble.