英语选择性必修二Unit 1 Grammar—predicative clause
人教版选择性必修第二册Unit1 单元整体教学课件语法课(第2课时)
• 2. What was Snow’s discovery in two particular streets in London? • The cholera outbreak was so severe that more than 500 people died
Activity 2
S+V+P
Can you find out the sentences with predictive clauses in the text on page 2&3? Then state their meaning and functions.
1.One theory was that bad air caused the disease.
②感官动词：sound, taste,smell, look, feel;
It looks as if he is unhappy today.
人教版（2019）选择性必修二
Unit 1 SCIENCE AND SCIENTISTS
• Period 2 Learning About Language 2
•Discover Useful Structures
Learning Objectives
• 1.To further grasp the structural features of predicative clauses and their ideographic functions.
water carried cholera germs / Water from the Broad Street pump had been infected by waste.
Unit 1 Scientists 语法 -高二英语(上外版2020选择性必修第二册)
Exercise
28. A dog named Laika was_k_n__o_w_n___ (know) as the first living thing to travel around the Earth. 29. Her job was_t_r_a_v_e_ll_i_n_g____ (travel) inside the spaceship and _le__tt_in__g__ (let) scientists monitor her heart rate, breathing, and blood pressure during the trip.
正在进行的一种具体动作，做谓语动词用。
Introduction of the Rules
1. Verb-ed 作表语时表示主语(人和事物) 所处的状态。
Ben seemed delighted at the thought of adopting of a cat. Our monitor was discouraged because of the criticism she received.
Homework
1. Complete the exercise on page 9 2. Complete Grammar exercise 3. Preview the informaiton on page 10
动词-ing形式: 有动词的特征，同时又具有名词、形容词和副词的特 征，因此它可以在句中作主语、表语、定语、宾语、宾语补足语和状 语。（又称现在分词，现在进行式，动名词)
动词-ed形式：由动词原形+ed构成（也有一些动词为不规则动词）， 也称为动词的过去分词。动词-ed形式仍保留着动词的特征，可以跟 宾语和状语。
高二上英语 选择性必修二Unit 1 Discover useful structures教学设计
通过文本中的不同活动让学生明白表语从句的功能；能完成关于表语从句的用法的练习。
教学流程
环节任务
教师活动
学生活动
设计意图及评价要点
Step 1
Lead in
1.Lead in the learning objectives;
2.Guide the students to review the predicative clauses.
Practice in class
Ask students to complete Activity 2&3 to consolidate what they have learned about thepredicative clauses.
Complete Activity 2&3 to consolidate what they have learned about thepredicative clauses.
Guide students to understand and consolidate their understanding of the thepredicative clauses.
Step 5
Self-evaluation
1.Show Ss the following questions:
4)Can you express your ideas by using the predicative clauses?
2.Ask Ss to check whether they have achieve the goals.
Check the goals:
1)Can you analyze the structure of the predicative clauses?
新人教版(2019)高中英语选择性必修第二册 Unit 1 grammar 表语从句PPT课件
表语从句的语法规则
The grammar rulers of the predicative clause
➢ I do so many things for you. It is because I love you. ➢ I am late this morning. That is because I left my bag on the subway. ➢ Your speech is excellent. This is because you prepared it a lot.
2.He was fired. That was __b_e_c_a_u_s_e_ he is careless and irresponsible.
3. The reason __w_h_y___ he was fired was __t_h_a_t___ he was careless and irresponsible.
Rule 1 : 表语从句和宾语从句、主语从句一样，要用陈述语序： 主语+谓语。
表语从句的语法规则
The grammar rulers of the predicative clause
The question is if it is worthwhile to do it. The question is whether it is worthwhile to do it.
Rule 5 :当从句描述原因时： ① 主语为reason 时，引导词用that ② It, This, That 开头做主语，引导词用because
表语从句的语法规则
The grammar rulers of the predicative clause
Unit 1 Using Language2 表语从句语法课 课件-高中英语选择性必修第二册
but to give up enthusiasm may wrinkle the soul. Nowadays, the spead of “sang culture” is popular among teenagers who are never
to do more than necessary and arouse people’s anxiety
What do you think of the two kinds of youth culture? Why? What kind of youth culture do you prefer? Why?
Discussion: Youth Culture
lying down/flat
involution
In my group, our opinion/idea is that... That’s because... It seems as if... The question/truth is ... ... is what really matters... Our suggestion is that... ...
引导词在从句中充当的成分？
在从句不做成分: that, whether, as if/as though, because
M: 我担心的是他能否从中抑郁消沉中走出来。 他看起来似乎对自己没有信心。
W: 那是因为他这个实验已经失败很多次了。 M: 我的建议是他可以向有经验的教授请教。
M: My concern is whether he can walk out of depression. It seems as if he has no confidence in himself.
人教版高中英语选择性必修第二册第一单元E2 U1 Grammar导学案
E2Unit1 Science and ScientistsGrammarMotto: The pursuit of science needs special courage. 追求科学需要特殊的勇敢。
Ⅰ. Learning aims1.To learn the structure of predicative clause.2.To know how to judge the predicative clause.3.To master the conjunctions of predicative clause.Ⅰ. ConsolidationLevel A 单句语法填空1.The truth is __________ we are lucky enough to have clean water whenever we want, but this is not the case for many people around the world.［浙江·月卷］2.This is __________ my father has taught me --- to always face difficulties and hope for the best.［北京卷］3.His advice to his grandma is________ she make good use of her spare time.4. The amazing thing about the spring is __________ the colder the temperature gets, the hotter the spring!［2021·新高考I卷］5. What puzzles Lily’s friends is __________ always has so many crazy ideas.［2021天津卷］Level B Complete the sentences.1. The fact was____________________________________ . 事实是他没有真正的去尝试。
高中英语人教版(2019)选择性必修第二册Unit 1表语从句课件
即学即练
1. My suggestion is that we _s_h_o_u_l_d__g_o_ (go) to hospital at
once. 2. When a pencil is partly in a glass of water, it looks as if it
_w__e_r_e__(be) broken. 3. My idea is that we _s_h_o_u_l_d_g_e_t__(get) more people to attend
4. as if/as though引导表语从句的【两种语气】
1.若表陈述语气，就用陈述语气； 2.若与客观事实不符，就用虚拟语气；
若跟现在事实不符：过去式（be动词用were） 若跟过去事实不符：had done 若跟将来事实不符：would/could+动词原形
Examples
1. It seems as if it _h_a_d__b_e__e_n(be) spring already. 2. It seems as if I _c_o_u_l_d__b_e(be) flying in the sky. 3. All this was 20 years ago, but it is as if it _h_a_d__b__e_e_n__(be)
主语从句和表语从句的【连接词】 类似
表语从句的【从属连接词】
注意1: 表语从句的引导词没有if !!! 只用wh连et接he词r ,不用if的情况 不同点
共同点
Wthheathter to do
没有意义
Whether……or not 介w词h后et的he宾r 语从句 是否，一般不用if替换 从句：句首的主语从句，表语从句，同位语从均句不作句子成分
【课件】Unit+1Discover+Useful+Structures+表语从句选择性必修第二册
4. —Are you still thinking about yesterday’s game?
—Oh, that’s _____. (高考题)
A. what makes me feel excited
B. whatever I feel excited about
C. how I feel about it
7. The reason__w_h_y__ he failed is __t_h_a_t___he was too careless.
To Sum up
引导词
What are the leading words of the
predicative clause?
how,that,why,where...
1. My belief is ____t_h_a_t___I will succeed by working hard. 2. The most pleasant thing of the rainy season is ___t_h_a_t__we can be entirely free from dust. 3. The problem is ____w_h_e_t_h_e_r____we can find them there.
从句完整，不少成分
6. (2020·全国2.语法填空.改编)This is __w_h_y____decorating with plants,fruits
（形容词） （副词）
4. Every student is in the classroom. （短语）
5. Your homework is to recite "quanxue". （不定式）
英语选择性必修二Unit 1 Grammar-Noun clause predicative
Science and Scientists
内容索引
Period Three Grammar—Noun clause：predicative clause
Байду номын сангаас
语 法 导 学 感悟规律 重点难点剖析
语法感知
感知以下课文原句，补全方框下的小题
1.One theory was that bad air caused the disease. 2.Another was that cholera was caused by an infection from germs in food or water. 3.It seemed that the woman liked the water from the pump so much that she had it delivered to her house every day. 4.The truth was that the water from the Broad Street pump had been infected by waste.
3.注意事项 (1)why和because引导的表语从句的区别
That’s why... 意为“那是……的原因”，强调结果
That’s because... 意为“那是因为……”，强调原因 I didn’t phone her，and that’s why she got angry with me.(强调“没打 电话”这一结果) 我没有给她打电话。那就是她对我生气的原因。 I didn’t phone her，and that’s because I got angry with her.(强调“生 气”这一原因) 我没有给她打电话。那是因为我生她的气了。
人教版英语必修2 unit 1 grammar 课件
5. The woman remembered the day. She saw the Nazis burying something near her home.
Mr. Black is the man who rescued me from the river.
Mr. Black, who is a doctor, rescued me from the river.
C. In Antecedent (先行词)
e.g. Mike sold the house which his family has lived in for 30 years.
3. She got so angry. I don’t know the reason.
I don’t know the reason why she got so angry.
4. The old man saw some Germans taking apart the Amber Room and removing it. You are talking to an old man.
Grammar
限制性定语从句和非限制性定语 从句 (Restrictive attributive clause and non-restrictive attributive clause)
Can you tell the difference between Restrictive and Non-Restrictive Clause?
新人教高中英语选择性必修二Unit1 Discover useful structures公开课教案
2019新人教高中英语选择性必修二Unit 1 Discover Useful Structures 公开课教案Teaching aims:By the end of the period, students will be able to:1.To analyse the forms and features of predicative clauses.2.To learn about the functions of predicative clauses in the context.3.To use predicative clauses in the given context.Teaching key and difficult points:1.Help students to analyse and use predicative clauses.2.Instruct students to use predicative clauses to express their own ideas.Teaching procedures:StepⅠLead-inIn those days,there were two contradictory theories to explain how cholera spread.One theory was that bad air caused the disease.Another was that cholera was caused by an infection from germs in food or water.Snow subscribed to the second theory.One evidence is that a woman and her daughter had died of cholera after moving away from Broad Street.It seemed that she liked the water from the pump so much that she had it delivered to her house every day.The truth was that the water from the Broad Street pump had been infected by waste.1.Can you find any predicative clauses?2.Why do you think they are predicative clauses?3.What are the main linking verbs?Suggested answers:1.In those days,there were two contradictory theories to explain how cholera spread.One theory was that bad air caused the disease.Another was that cholera was caused by an infection from germs in food or water. Snow subscribed to the second theory.One evidence is that a woman and her daughter had died of cholera after moving away from Broad Street.It seemed that she liked the water from the pump so much that she had it delivered to her house every day.The truth was that the waterfrom the Broad Street pump had been infected by waste.2.Because there are linking verbs closely before the predicative sentences.3.Linking verbs{状态类:be,seem,appear,keep,remain, stay...感官类:look,smell,taste,sound,feel...变化类:become,get,turn,grow,fall, come,go...StepⅠObserve and analyseActivity 1Ask and answer the questions in pairs using the information from the reading passage.(P5 Activity 2)（红色部分为学生作答）1.What was Snow’s discovery in two particular streets in London?Snow’s discovery in two particular streets in London was that the cholera outbreak was so severe that more than 500 people died in ten days.2.What was Snow determined to find out during the 1854 outbreak of cholera in London?What Snow was determined to find out was why so many people died/the outbreak of cholera had caused over 500 deaths within ten days.3.What were the exact places Snow marked on the map?The exact places Snow marked on the map were where all those who died had lived/ all the dead people had lived.4.What was the finding that Snow announced?Snow’s finding was that the pump water carried cholera germs/ the water pump was to blame for the spread of cholera.Activity 2Fill in the blanks.1.Snow’s discovery in two particular streets in London was that the cholera outbreak was so severe that more than 500 people died in ten days.2.What Snow was determined to find out was why so many people died.3.The exact places Snow marked on the map were where all those who died had lived.4.Snow’s finding was that the pump water carried cholera germs.Activity 3Fill in the form.引导词that which whether w hat who As if/asthoughwhy when where how作的成分不作成分定语表语不作成分主语宾语表语定语主语宾语表语不作成分状语状语状语状语意思无意思哪一个是否什么谁好像为什么什么时候在哪里如何;怎样Step Ⅰ PracticeActivity 1Complete David’s lines(A~E) by filling in guiding words.(P5 Activity 3) as if that what who when how why whosewhich whetherA.Absolutely.You may not believe it,but that was happened at the initial stage of our group’s research on developing a vaccine for malaria.B.Yes,it is.And it seemed all the theories were useful,but the fact was we couldn’t persuade one another that one theory was better than another.C.Exactly.The problem was not about all our theories were equally good,but in deciding theory to depend upon.D.We realized that what we cared about was not aspect we needed to develop a theory in,but rather we can reduce the cost of a vaccine without reducing its effect!E.You’re right.At last,we became focused on the key issue,which was we had to carry out the research in the first place.Suggested answers:A:what B:as if;that C:whether;whose/which/what D:which/what;how E:whyActivity 2Put A~E in the correct order using the above methods.Then check the answers and state the reasons.(P5 Activity 3)A.Absolutely.You may not believe it,but that was what happened at the initial stage of our group’s research on developing a vaccine for malaria.B.Yes,it is.And it seemed as if all the theories were useful,but the fact was that we couldn’t persuade one another that one theory was better than another.C.Exactly.The problem was not about whether all our theories were equally good,but in deciding whose theory to depend upon.D.We realized that what we cared about was not which aspect we needed to develop a theory in,but rather how we can reduce the cost of a vaccine without reducing its effect!E.You’re right.At last,we became focused on the key issue,which was why we had to carry out the research in the first place.Maria:This mix of theory and data is one of the key characteristics of what we call science.David:______________________________Reason:______________________________Maria:With your theoretical framework?David:________________________________Reason:__________________________________Maria:Deciding on a theory is definitely of critical importance.David:_____________________________________Reason:____________________________________Maria:This was when you should have calmed down and got down to doing some solid work.David:__________________________________________Reason:_________________________________________Maria:So what happened in the end?David:__________________________________________Reason:________________________________________Suggested answers:A(Logical connector)C(Lexical connector) B(Grammatical connector) E(Logical connector) D(Grammatical connector)Activity 3Answer the following questions about the dialogue using the predicative clauses.1.What was David’s group’s research?2.What was the problem?3.What was the key issue?4.What did they care about?Suggested answers:1.David’s group’s research was that they wanted to develop a vaccine for malaria.2.The problem was that they had to decide which theory to depend upon.3.The key issue was why they had to carry out the research in the first place.4.What they cared about was how they could reduce the cost of a vaccine without reducing its effect.StepⅠ Language use and shareActivity 1Work in plete the conversations using the predicative clauses.Every group can choose one or two dialogues,and each member must complete at least two predicative clauses.1.A:Paper making,printing,gunpowder,and the compass are the four great inventions of ancient China.They are significant contributions of the Chinese nation to the world.B:Sure,they are.What I want to know though is .2.A:The ancient Chinese were the first to invent paper and printing.Then they went on to invent books and had opened bookshops in many cities.B:What I’m curious about is .3.A:The compass is a special invention of ancient China,dating back to as early as the Warring States Period.B:Yes.It seems .4.A:Gunpowder was originally used for making fireworks.B:But what surprises me is .5.A:High-speed trains,mobile payments,the bike-sharing system,and online shopping are considered by some as the new “four inventions” of China.B:Is that so? I feel/It seems .Suggested answers:1.which one is the greatest invention/how these inventions have changed China and the world2.who invented paper/how people made the first paper/when ink was invented/what paper was made from/when and how printing spread to the rest of the world/how records were kept before the invention of paper3.that the compass was particularly useful/as if people had to depend on the positions of the sun,the moon,and so on when they were at sea before the compass was invented/that ancient Chinese had developed a good knowledge of magnetism4.that gunpowder was not used initially for firearms/how it is so unexpectedly used today/how heavily mining depends upon it/that it has been generally used not only in industries but in wars across the world5.that these inventions have really made our lives easier/that every Chinese is proud of the new “four inventions”/as if I could not live without them,especially when it comes to online shopping/that we all benefit from all these things/that we may have to remember that every coin has two sidesStepⅠconsolidationⅠ.Fill in the blanks with guiding words.1.Look at the tallest building.That is my father works.2.One of the most exciting moments in my life was I won first place in the singing competition.3.Now,the only problem is we can collect enough money for the project.4.One advantage of solar energy is it will never run out.5.What is troubling me is I don’t have much experience of this kindof work.6.That’s you are wrong.You forgot Step Three.Ⅰ.Choose the best answer.1.Without his support,we couldn’t be we are now.A.howB.whenC.whereD.why2.This is my father has taught me—to always face difficulties and hope for the best.A.howB.whichC.thatD.what3.By boat is the only way to get here,which is we arrived.A.whereB.whenC.whyD.howSuggested answers:Ⅰ 1.where 2.when 3.whether/how/when 4.that 5.that 6.where/whyⅠ 1.C 2.D 3.D。
Unit 1 Grammar 表语从句讲义-高中英语人教版选择性必修第二册
高中英语人教版选择性必修第二册unit 1 Grammar表语从句(ThePredicative Clause)一、表语从句的定义：表语从句就是用一个句子作为表语，放在连系动词之后，充当复合句中的表语，用来说明主语是什么或者怎么样。
The problem is puzzling.主语连系动词形容词作表语The problem is when we can get a pay rise. 主语连系动词一个句子作表语一表语从句二、表语从句的构成：系动词+引导词+简单句What I want to say is that I am tired.三、表语从句的用法.可按表语从句的连系动词有：1).最常用连系动词：be(am; is/was; are/were)o一般在句子中译成：“ 日”7E ...China is no longer what she used to be.2).表变化的系动词：get; turn; go; fall; become; grow; come; run。
用法注意：在英语中，系动词一般只有一般现在时和一般过去时两种时态变化形式，没有其他时态变化形式。
但表变化的这类系动词除外，它们有各种时态变化。
It is becoming colder and colder. The food has gone bad.此处还需注意的是become和turn后接表职业的名词时冠词的有无：Two years later, he became a teacher.但Two years later, he turned teacher.另外，g。
表变化时一般指事情向消极、不好的方面转化。
3).所谓“感官动词”:look; sound; ta ste; smell; fbeL般它们在句子中译成:“・・・起来; ...上去”。
此类系动词为高考高频词。
The food tasted good.食物尝起来很香。
新人教高中英语选择性必修二Unit1 Discover Useful Structures公开课课件
Teaching objectives:
By the end of this period, you will be able to…
1. Analyze the forms and features of predicative clause. 2. Learn the functions of predicative clause in the context. 3. Use predicative clause in the given context.
_o_f__c_h_o_le_r_a_h__a_d_c_a_u_s_e_d_o_v_e_r__5_0_0_d_e_a_t_h_s_w__it_h_i_n_t_e_n_d__a_y_s._. 3. What were the exact places Snow marked on the map? The exact places Snow marked on the map were where _a_l_l _th_o_s_e__w_h_o__d_ie_d__h_a_d__li_v_e_d_/
2. What Snow was determined to find out was__w_h_y__ so many people died.
3. The exact places Snow marked on the map were _w__h_e_re__ all
those who died had lived.
D. We realised that what we cared about was not _w_h_a_t_/w__h_ic_h_ aspect we needed to develop a theory in, but rather ___ho_w____ we can reduce the cost of avaccine without reducing its effect! E. You're right. At last, we became focused on the key issue, which was
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Period Three Grammar—Noun clause：predicative clause感知以下课文原句，补全方框下的小题以上4个句子中的黑体部分都是从句，这些从句在词性上相当于一个名词，故被称作名词性从句，而且从句作表语，所以又被称作表语从句。
一、名词性从句1．概念：在主从复合句中，相当于名词的从句被称为名词性从句。
2．分类：名词性从句包括：主语从句、宾语从句、表语从句和同位语从句。
3．连接词4.注意事项(1)名词性从句要用陈述语序；(2)主从句的时态要基本呼应，有时需用虚拟语气；(3)注意某些连接词的特殊用法(见后)。
二、表语从句1．概念：在主从复合句中充当表语的从句，叫作表语从句。
它常位于系动词之后，用来说明主语是什么或怎么样。
2．连接词的用法(1)that引导的表语从句用法：①无意义②不充当成分③不可省略The trouble is that she has lost his address.麻烦的是她弄丢了他的地址。
My suggestion is that we should tell him.我的建议是我们应该告诉他。
(2)whether引导的表语从句The question remains whether they will be able to help us.问题还是他们能否帮我们。
[名师点津]if不能引导表语从句。
(3)连接代词和连接副词引导的表语从句The problem is how we can find him.问题是我们如何找到他。
He is no longer what he was.他已经不再是以前的他了。
That’s where you are wrong.那就是你不对的地方。
(4)because，as if/as though等引导的表语从句It sounds as if someone is knocking at the door.听起来好像有人在敲门。
That’s because you can’t appreciate music.那是因为你不会欣赏音乐。
3．注意事项(1)why和because引导的表语从句的区别I didn’t phone her，and that’s why she got angry with me.(强调“没打电话”这一结果)我没有给她打电话。
那就是她对我生气的原因。
I didn’t phone her，and that’s because I got angry with her.(强调“生气”这一原因)我没有给她打电话。
那是因为我生她的气了。
(2)表语从句中的虚拟语气在表语从句中，表示间接的命令、要求、请求、建议、决定等，主句中的主语通常是：advice，suggestion，proposal，request，order，idea等，从句谓语形式是“should＋动词原形”(should 可以省略，但不可换成would)。
My suggestion is that we (should) start early tomorrow.我的建议是我们明天一早就出发。
Ⅰ.补全句子1．The fact was that he didn’t really try.事实是他没有做真正的努力。
2．The question is whether the film is worth seeing.问题是这部电影是否值得看。
3．Now it seems as though/if she has known Millie for years.现在看起来好像她认识米莉已有好多年了。
4．My advice is that you (should) practise speaking English as often as possible.我的建议是你尽可能经常地练习说英语。
5．That’s where I first met her.那就是我第一次遇见她的地方。
6．The problem is who is really fit for the hard job.问题是谁才真正适合做这份艰苦的工作。
7．That is why I want you to work here.那就是我想让你在这儿工作的原因。
8．I was late for school this morning.That’s because I stayed up too late last night.今天早上我上学迟到了。
那是因为我昨晚睡得太晚了。
Ⅱ.语法填空(用适当的连接词填空)Everyone knew 9.that Wendy was a famous writer，but no one knew 10.where she came from and 11.whether she was born in 1961 was still a mystery.12.What they did know was 13.that she was loved by poor people because she always helped 14.whoever was in need of money.Wendy was generous and helpful，but some people thought she was chasing fame.Wendy said she didn’t understand 15.why they were so narrowminded，but it didn’t matter 16.what others thought ofher.She just wanted to do 17.what(ever) she thought was right.She thought that was 18.where the meaning of life lied.基础巩固Ⅰ.选用适当的连接词填空that；why；whether；what；as if；whatever；because；when；how1．You must do whatever is best for you.2．The trouble is that I lost the key to my room.3．I am not sure whether he is willing to help me.4．I’m a bit sleepy，it’s because I was up all night.5．Do you remember when/how/why he came here?6．I’m wondering why you are always late for class.7．We think that it’s necessary to talk with him again.8．The question discussed at the meeting was whether it was worth trying.9．All this was over twenty years ago，but it is as if it were only yesterday.10．My parents are very kind to me and always let me do what/whatever I think I should do.Ⅱ.完成句子11．That’s why I think(那就是我认为……的原因) the trip along the Yangtze River will be a better choice.12．And you also should keep it in mind that exchanging notes with your classmates frequently is a good way to improve your study(和同学经常交流笔记是提高学习的好方法)．13．All the participants can get what they want(他们想要的东西)．14．In such a case I will insist on whatever I think is right(我认为正确的任何事情)．15．To practice as much as possible is where the secret lies(秘密所在)．16．You need to hand in a report，explaining how the idea occurred to you(你怎样想到的这个主意) and what materials you used.17．I’m wondering whether/if you would like to spend this time with us(你是否愿意和我们度过这段时光)．能力提升Ⅲ.阅读理解APeople have been wondering why elephants do not develop cancer even though they have lifespans(寿命) that are similar to humans，living for around 50 to 70 years.Now scientists believe they know why.A team at the University of Chicago，US has found that elephants carry a large number of genes that stop tumors(肿瘤) developing.To be precise，they found 20 copies of an antitumor gene called TP53 in elephants.Most other species，including humans，only carry one copy.According to the research，the extra copies of the gene improved the animal’s sensitivity to DNA damage，which lets the cells quickly kill themselves when damaged before they can go on to form deadly tumors.“An increased risk of developing cancer has stood in the way of the evolution of large body sizes in many animals，” the study author Dr Vincent Lynch told The Guardian.If every living cell has the same chance of becoming cancerous(癌变的)，large creatures with a long lifespan like whales and elephants should have a greater risk of developing cancer than humans and mice.But across species，the risk of cancer does not show a connection with body mass.This phenomenon was found by Oxford University scientist Richard Peto in the 1970s and later named “Peto’s paradox(悖论)”．Biologists believe it results from larger animals using protection that many smaller animals do not.In the elephant’s case，the making of TP53 is nature’s way of keeping this species alive.The study also found that when the same genes were brought to life in mice，they had the same cancer resistance as elephants.This means researchers could use the discovery to develop new treatments that can help stop cancers spreading or even developing in the first place.“Nature has already figured out how to prevent cancer，” said Joshua Schiffman，a biologist at the School of Medicine，University of Utah，US.“It’s up to us to learn how different animals deal with the problem so that we can use those strategies to prevent cancer in people.”18．Why are elephants unlikely to develop cancer?A．They have a rather large body size.B．Their genes suffer no DNA damage.C．Certain genes in their body kill existing tumors.D．They carry many genes to prevent tumors developing.答案D解析细节理解题。