教材习题点拨 COMPREHENDING ☞Suggested answers to Exercise 1：
1 The first use is to produce commercial quantities of plants.The second is to research on new plants species and do medical research on animals. 2 Cloning plants is straightforward，but the cloning of animals is very complicated. 3 The first clone from an adult animal was Dolly the sheep.She died in 2003. 4 Cloning is controversial in some countries for moral and religious reasons. ☞Suggested answers to Exercise 2：
Problems or dangers of cloning Advantages of cloning Animal clones may develop the illnesses of older animals. Medical cloning could produce cures for serious illnesses in humans. Animal clones may die younger than the donor animals. Cloning plants can produce plants of similar quality for sale. Evil leaders may want to clone themselves. Cloning plants can be useful for research on new plant species. There are moral objections to cloning human beings. Cloning can help save endangered animals. ☞Suggested answers to Exercise 3：
I think the writer is impartial because he/she does not state any personal opinion about cloning. LEARNING ABOUT LANGUAGE Discovering useful words and expressions ☞Answers to Exercise 1：
1 differ 2 cast 3 accumulate 4 exact 5 altogether 6 objections 7 undertake 8 moral ☞Answers to Exercise 2：
1 Compared with her family，and especially her nephew，her niece Daisy is straightforward about her opinions. 2 The arbitrary decisions of the factory leaders caused anger among the workers. 3 Is the opera house in the commercial area of Beijing? 4 The producer of the media programme made_an_objection_to Jennifer joining in the chorus. 5 Before you can make a loaf，you need to obtain some flour. 6 You owe the lady an apology.I will_forbid you to leave unless you apologize for what you have done. ☞Answers to Exercise 3：
1 attain 2 complicated 3 fate 4 carrier 5 cast 6 reform 7 accumulate Discovering useful structures ☞Answers to Exercise 1：
1 The whole scientific world followed the progress of the first successful clone，Dolly_the_sheep. 2 Then came the disturbing news that_Dolly_had_become_seriously_ill. ☞Answers to Exercise 2：
Dolly the sheep became a scientific breakthrough when the news that_she_had_been_born was announced in 1997.However，the problem that_she_later_developed_a_serious_lung_disease bothered scientists.On 14th February 2003 scientists made the decision that_Dolly_should_be_put_to_sleep.Dolly＇s death，like her birth，was bound to raise worries.The fact that_Dolly_died_when_she_was_quite_young disappointed people the world over.Scientists hold the belief that_cloning_may_lead_to_many_important_scientific_breakthroughs_and_ medical_treatments.But now the question comes to their minds，“Did_she_die_young_because_she_was_a_clone？”Besides that，there is also a fierce debate over the question whether_human_cloning_experiments_should_be_allowed.Scientists believe human cloning is just a matter of time but the assumption that_human_clones_have_already_ been_born hasn＇t been proved yet. 1997年多莉羊诞生的消息宣布后便成为一项科学突破。但是，后来多莉染上严重肺病的问题又使科学家们忧虑。2003年2月14日科学家们作出让多莉羊长眠的决定。多莉之死正如它的出世一样，肯定会带来焦虑。多莉早亡的事实令世人失望。科学家们认为克隆可能会带来很多重大的科学突破和医学疗法，但是现在他们不得不思考这样的问题：“多莉早死是因为它是一只克隆羊吗？”除此以外，关于是否应该允许进行人类克隆实验的问题也引起了激烈的争论。科学家们相信人类的克隆只不过是时间问题，但是克隆人已经问世的说法还没有被验证实。
☞Suggested answers to Exercise 3：
Numerous answers are possible but all the clauses in the appositive should begin with the word“that”． 1 I have no idea that_she_would_come_next_week_for_a_short_visit. 2 We heard the news that_a_woman_trapped_under_the_ruins_for_six_days_was_rescued. 3 John told the truth that_he_failed_in_the_test. 4 Betty won a prize that_she_had_dreamed_of_for_years. 5 Charles agreed to the regulation that_he_must_have_safety_training. 6 Yesterday I was glad to get a message that_the_interview_went_well. 7 The fact that_the_people_in_the_earthquakehit_areas_had_rebuilt_their_homes_inspired_ all_of_us. 8 I got the impression that_everyone_in_class_did_well_in_the_performance. USING LANGUAGE Reading，discussing and writing ☞Suggested answers to Exercise 1：
1 There will not be enough genetic variation in the group to be able to resist new illnesses. 2 It is not a good idea to clone an animal that would live in a zoo because it is not a suitable habitat to develop and increase its numbers.The zoo is not a natural environment for a wild animal. ☞Suggested answers to Exercise 2：
Cloning is useful because ·it could find a cure for illnesses that are presently incurable；
·it means that endangered species can be preserved；
·it could help families who cannot have children of their own. It is a bad thing because ·it might produce monsters；
·it might bring back to life creatures that might harm us；
·you might be cloned without your knowledge. Listening and speaking LISTENING TEXT IS CLONING CRUEL? Xiao Qing(XQ)and Rachel Brown(RB)are discussing whether cloning is cruel to animals or not. RB：Xiao Qing，do you think cloning＇s cruel? XQ：What do you mean by that？The scientists are doing a wonderful job.Soon they may be able to bring people＇s favourite pets back to life! RB：Yes，I know.But doesn＇t it seem cruel to you that it took 276 experiments before Dolly was successfully cloned？Think of all those live cells and eggs that died in order for Dolly to be born.I don＇t approve of that! XQ：But，Rachel，be reasonable.Isn＇t it always like that with a new science？This is the way people learn to do things better. RB：I suppose so—but they also make the animals do such unnatural things.One poor cow was made to give birth to a bison.What was the poor creature to think when it saw its baby? XQ：I don＇t quite understand why so many people are against cloning.I think the scientists need a bit of encouragement.Think of the benefits.Cloning may be medical science to produce cures for serious illnesses. RB：Yes，I know and I agree with that.It＇s just that I don＇t agree with the methods. XQ：Why not? RB：Well，I think it＇s a dead end.Dolly the sheep was“middleaged”when she was born because her DNA came from a middleaged “mother”．Cloning your grandmother would mean a new baby started life as an old lady! XQ：Really？I never thought of that! RB：And it weakens the species.Cloning means that there＇s less variety in the species.So the animals may not be able to resist a particular illness and they might die out. XQ：Oh dear！And that was just what you and I were trying to avoid.In spite of all these，don＇t you think scientists would still be able to solve the problems? ☞Answers to Exercise 1：
1 3 4 5 ☞Suggested answers to Exercise 2：
Rachel＇s ideas about cloning Xiao Qing＇s ideas about cloning 1 cruel to animals 1 scientists are doing a wonderful job 2 makes the animals do unnatural things 2 may bring people＇s favourite pets back to life 3 it is a“dead end” 3 problems because it is a new science 4 weakens the species 4 it may provide cures for serious illnesses 练习册答案及听力原文 Unit 2 Cloning LISTENING LISTENING TEXT IS HUMAN CLONING A GOOD IDEA? Wang Qiao(WQ)is talking to Clare Peters(CP)about human cloning. WQ：What do you think about human cloning，Clare? CP：I don＇t know what to think.But I suppose it＇ll come one of these days.I think there are many problems that nobody has thought of yet. WQ：What do you mean by that? CP：Well，a clone will be an exact copy of the original donor.Right? WQ：Yes，so what? CP：Well，what＇s the relationship between the clone and his original donor? WQ：I suppose they must be like one person.The clone is the same as his original donor. CP：Let＇s suppose that you take a baby to a laboratory to be cloned.Does it matter if the laboratory returns you the real baby and one clone or two clones? WQ：Yes，it does.But how could this possibly happen? CP：Well，the scientists may get confused. WQ：My goodness.Surely they would notice if there is an agegap between the donor and the clone. CP：Maybe.What if the donor and the clone are very close in age? Let us suppose they are both babies. WQ：OK. CP：Let＇s suppose that the laboratory wanted to use the real baby to make more clones.Perhaps they know parents who would like to buy a cloned baby.Perhaps this family is unable to have children of their own.So the laboratory keeps the real baby and sells the clones as they grow. WQ：But that＇s a baby factory！That＇s not moral at all! CP：I know，and that＇s why it＇s important to get our ideas sorted out now.So we really have to think about the problems of human cloning. WQ：Yes.Now I see your point.We should do something about this.How about a class discussion？What do you think？...(fade out) ☞Answers to Exercise 2：
2 3 4 ☞Suggested answers to Exercise 3 1 Clare thinks people will want to buy cloned babies if they cannot have babies of their own. 2 People have not thought that there may be dishonest laboratories who will produce and sell cloned babies like a baby factory. 3 Various answers are possible but each needs a reason to be considered correct. 4 Various answers are possible but each needs a reason to be considered correct. USING WORDS AND EXPRESSIONS ☞Answers to Exercise 1：
procedure，assumption，be bound to，resist，from time to time，restoring，shortly，claws，brought back ☞Answers to Exercise 2：
1 in time 2 in danger 3 in vain 4 in black pen 5 in favour of 6 In the meantime ☞Suggested answers to Exercise 3：
1 I adore homemade rectangular loaves made with brown flour and nuts. 2 He is very conservative，and is even in favour of a constitution that gives few rights to immigrant voters. 3 When the leader of the chorus retired from the opera，they held a dinner party for him. 4 The media plays an important role in influencing public opinion. 5 Don＇t bother about taking down those decorations yet.The Christmas celebrations aren＇t over yet. 6 The regulations for cloning animals are very strict.He was unable to continue his experiments. 7 Don＇t bother yourself about cloning my pet cat.I won＇t expect to bring it back to life. 8 The people in flooded areas owed a great deal to the PLA soldiers for their rescue work. USING STRUCTURES ☞Answers to Exercise 1：
1 C 2 E 3 A/F 4 B 5 A/F 6 D The first sentence does not contain an appositive clause，but an objective clause. ☞Answers to Exercise 2：
1 that they should buy a new car 2 that they wanted the most expensive one 3 that they would save for six months 4 that Sue＇s uncle had died unexpectedly 5 that she must follow when she inherited money 6 that she should save all her money in the bank 7 that she was doing the right thing to use the money Appositive clauses：1 3 4 ☞Suggested answers to Exercise 3：
Hans Lotte，the_explorer，is wellknown for his excellent television documentaries.However，he does not look like a traditional television host，so many people cannot understand how_he_got_his_job.The fact that_mountain_climbing_was_so_popular_in_his_hometown_in_Florida encouraged his ambition.It made him interested in television documentaries that_he_both_could_take_risks_and_earn_a_living.So he made the decision that_he_would_study_earth_sciences_at_university.Luckily the possibility that_he_spoke_many_languages helped him become a star when the TV company visited Russia.he soon became a regular presenter in front of the camera and viewers began to ask why_he_did_not_make_it_his_career.He became a great success.Unhappily we have heard the news that_he_is_retiring_this_year，but everybody can still watch his fascinating series on TV. LISTENING TASK LISTENING TEXT A DISCUSSION ABOUT CLONING Billy(B)and Frank(F)are having a discussion about cloning pets. B：You know，Frank，I agree with cloning.My mum has a pet dog and she is devoted to her.I think if anything happened to this pet she would be very upset.So we want to keep my mother happy by keeping her pet alive forever! F：What＇s this all about？A little dog！Surely you can make your mother happy again in another way！Does she know what people did before cloning was a possibility? B：Yes，and she knows the cloning procedure.She＇s read about the experiments in America.They offer chances for pets to produce their own stem cells.These stem cells will produce new pets at a very reasonable price. F：Reasonable price！Surely it will be very expensive. B：Well，my mother is saving money to go to America with the dog just before it dies.If she goes to the laboratory，we＇ll all spend a week in America.If we＇re lucky，we＇ll be able to return after a few months with a new dog. F：Now I understand.You just want a holiday trip to America，and getting a new dog is just an excuse. B：Yes and why not? F：You are encouraging your mother to love her dog，so she will want to clone it when it gets old.Then you will take advantage of that to have a good holiday.Don＇t you think about the moral problems of cloning? B：No，I don＇t.It＇s fine by me，if I can make my mother happy and enjoy myself as well.That＇s moral too! F：You know what they say about small dogs in Western countries.People keep dogs instead of having a real baby.Is that the case with your mother? B：Certainly not！She has me after all.But I have to be away from her when I study abroad for my Master＇s degree.She＇ll need her small dog then! F：I see.Now I know why I don＇t agree with cloning. B：Now you know why I do. ☞Answers to Exercise 2：
1 O 2 O 3 F 4 O 5 F 6 O 7 F 8 O 9 O 10 F ☞Suggested answers to Exercise 3：
1 He wants to make his mother happy by keeping her pet dog alive forever，and he also wants to take the chance to America for holiday when the dog is being cloned there. 2 Frank doesn＇t agree with cloning because he thinks cloning is very expensive and it has many moral problems. 3 Billy＇s mother is in favour of cloning.She is saving money to go to America to have her pet dog cloned just before it dies. 4 Various answers are possible. ☞Suggested answers to Exercise 4：
Billy＇s arguments for cloning pets Frank＇s arguments against cloning pets 1 It is moral to make my mother happy. 1 It is very expensive to clone a pet. 2 It can provide an excuse for a holiday abroad. 2 It is selfish because it is an excuse for a holiday. 3 My mother will need her pet when I am away. 3 It is selfish because it means the student can study abroad without his mother complaining. ☞Answers to Exercise 5：
BILLY：Yes，and she knows the_cloning_procedure.She＇s read about the experiments_in_America. FRANK：You are encouraging your_mother_to_love_her_dog，so_she_will_want_to_clone_it_when_it_gets_old.Then you will take_advantage_of_that_to_have_a_good_holiday. WRITING TASK ☞Sample writing：
Yesterday there was a very exciting debate at Xinjiang Middle School about whether medical cloning should be allowed or not.After a lively discussion a vote was taken and the side arguing for medical cloning won. The arguments for medical cloning were very strongly put by the team supporting the motion.They argued that serious illnesses and people who were losing their ability to move or think could be helped by medical cloning.They explained that the procedures would be safe，quick and with no problems for the patients.They showed that 67% of the people in America supported it.Their arguments were very convincing. The arguments put by the team opposing medical cloning were less strong.They argued in two ways.Their first reason was that the procedures were not yet secure.Their second reason was that it took many tries and many potential animals had to be killed to produce one useable embryo for research.They explained that more than twenty European countries do not allow medical cloning research because of this.They quoted Pope John Paul Ⅱ.But their arguments were not so convincing. At the end of the debate，the audience were left with a feeling of hope.They realized that diseases that seem terrible today may be able to be cured soon.Many people were excited and happy when they left the hall.The writer of this article was among them!
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