必修二 第四单元 Wildlife Protection 拓展阅读

必修二第四单元Wildlife Protection拓展阅读唐山市第二中学熊伟教学目标1）知识目标：学生学会找到段落的关键词，通过关键词总结段落大意；然后总结篇章大意。

学生观察发现本单元相关词汇并总结相关话题的新词汇，通过文章的句子对词汇进行理解学习运用。

2）能力目标：学生通过一系列的练习，能够总结出文章的主旨大意，提高其高阶阅读微技能之一——总结文章中心内容的能力。

3）情感目标：学生通过pair work, group work的形式讨论共同完成各项练习，增强合作意识；学生通过与本单元话题相关的阅读，增强动物保护的意识。

教学重难点学生在阅读过程中能够找段落关键词总结文章大意。

教学步骤Step 1：Lead-inToday we will learn how to find the key words in the paragraphs and get the main idea of a passage.(设计思想：直接告诉本课授课内容，学生可以有针对性得学习)Step 2：Presentation & Practice设问形式：1.标题类(1)The best title/headline for the passage is ________.(2)Which of the following is the best title?(3)What would be the best title for the text?...2.中心内容类(1)The passage is mainly about_______?(2)The main idea of the passage is _________.(3)The article mainly talks about__________.(设计思想：让学生知道这类题是怎样提问的。

)Step3. Dealing with two passagesA①The African elephant, the largest land animal remaining on earth, is of great importance to African ecosystem(生态系统). Unlike other animals, the African elephant is to a great extent the builder of its environment. As a big plant-eater, it largely shapes the forest-and-savanna(大草原)surroundings in which it lives, therefore setting the terms of existence for millions of other animals that live in its habitat(栖息地).②It is the elephant's great desire for food that makes it a disturber of the environment and an important builder of its habitat. In its continuous search for the 300 pounds of plants it must have every day, it kills small trees and underbushes, and pulls branches off big trees. This results in numerous open spaces in both deep tropical forests and in the woodlands that cover part of the African savannas. In these open spaces are numerous plants in various stages of growth that attract a variety of other plant-eaters.③Take the rain forests for example. In their natural state, the spreading branches overhead shut out sunlight and prevent the growth of plants on the forest floor. By pulling down trees and eating plants, elephants make open spaces, allowing new plants to grow on the forest floor. In such situations, the forests become suitable for large hoofed plant-eaters to move around and for small plant-eaters to get their food as well.1) The analysis of passage AparagraphKey wordsMain ideawho/what how①African elephantecosystemimportanceThe African elephant is of great importance toAfrican ecosystem.②elephant‟s desirefor fooddisturberbuilderThe elephant‟s great desire for food makes theelephant a disturber of the environment and a builderof its habitat.③rainforestsTake forexmpleTake rainforests for example to explain the reason.（设计思想: 学生通过小组合作的方式找出关键词并总结出各个段落大意）2) Exercise.1 . What is the passage mainly about?A. Disappearance of African elephants.B. Forests and savannas as habitats for African elephants.C. The effect of African elephants' search for food.D. The eating habit of African elephants.3)Picking out the words which appear in Unit 4 and which is new to the students.4)Using one of the new words to make a sentence.Main idea:The African elephant is of great important to African ecosystem,because the elephant‟s great desire for food makes the elephant adisturber of the environment and a builder of its habitat. And takerainforests for example.Main idea: China, in which panda is in danger of becoming extinct, is trying to clone the animal and save the endangered species, which is a move similar to a project called “Noah ‟s Ark ”. They are trying to save the animal that face extinction. (设计思想：巩固拓宽学生词汇量)B①With only about 1, 000 pandas left in the world, China is desperately trying to clone the animal and save the endangered species. That‟s a move which is similar to what a Texas A & M University researchers have been undertaking for the p ast five years in a project called “Noah‟s Ark”.②Noah‟s Ark is aimed at collecting eggs, embryos(胚胎), semen and DNA of endangered animals and storing them in liquid nitrogen(液氮). If certain species should become extinct(灭绝), Dr. Duane Kraemer, a professo r in Texas A & M‟s College of V eterinary Medicine, says there would be enough of the basic building blocks to reintroduce the species in the future.③It is estimated that as many as 2, 000 species of mammals, birds and reptiles will become extinct in over 100 years. The panda, native only to China, is in danger of becoming extinct in the next 25 years.④This week, Chinese scientists said they grew an embryo by introducing cells from a dead female panda into the egg cells of a Japanese white rabbit. They are now trying to implant(移植) the embryo into a host animal. The entire procedure （程序） could take from three to five years to complete. “The nuclear transfer(核子移植) of one species to another is not easy, and the lack of available panda eggs could be a major p roblem,” Kraemer believes. “They will probably have to do several hundred transfers to result in one pregnancy (having a baby). It takes a long time and it‟s difficult, but this could be groundbreaking science if it works. They are certainly not putting any live pandas at risk, so it is worth the effort,” adds Kraemer, who is one of the leaders of the Project at Texas A & M, the first -ever attempt at cloning a dog.1).The analysis of passage BparagraphKey words Main ideawho/what how①Chinaclone &save similarChina is trying to clone the animal and save the endangered species and it is a move similar to a project called “Noah ‟s Ark ”.② Noah ‟s Ark aim at &storeNoah ‟s Ark is aiming at collecting eggs, embryos, semen and DNA of endangered animals and store them③pandain danger of becoming extinctPanda in China is in danger of becoming extinct. ④we: China andNoah ‟s ArksaveChina and Noah ‟s Ark are both trying to save animal that face extinction.（设计思想: 学生通过小组合作的方式找出关键词并总结出各个段落大意）2) Exercise.2. What is mainly discussed in the text? A. China ‟s success in panda ‟s cloning B. The first cloned panda in the world C. A great project named Noah ‟s Ark D. The research into pandas cloning3) Picking out the words which appear in Unit 4 and which is new to the students. 4) Using one of the new words to make a sentence.(设计思想：巩固拓宽学生词汇量)Step4. Homework.CIt was a village in India ．The people were poor ．However, they were not unhappy ．After all, their forefathers had lived in the same way for centuries ．Then one day, some visitors from the city arrived ．They told the villagers there were some people elsewhere who liked to eat frog's legs ．However, they did not have enough frogs of their own, and so they wanted to buy frogs from other places ．This seemed like money for nothing ．There were millions of frogs in the fields around, and they were no use to the villagers ．All they had to do was catch them ．Agreement was reached, and the children were sent into the fields to catch frogs ．Every week a truck arrived to collect the catch and hand over the money ．For the first time, the people were able to dream of a better future ．But the dream didn't last long ．The change was hardly noticed at first, but it seemed as if the crops were not doing so well ．More worrying was that the children fell ill more often, and, there seemed to be more insects around lately ．The villagers decided that they couldn't just wait to see the crops failing and the children getting weak ．They would have to use the money earned to buy pesticides （刹虫剂 ）and medicines ．Soon there was no money left ．Then the people realized what was happening ．It was the frog ．They hadn't been useless ．They had been doing an important job-eating insects ．Now with so many frogs killed, the insects were increasing more rapidly ．They were damaging the crops and spreading diseases ．Now, the people are still poor ．But in the evenings they sit in the village square and listen to sounds of insects and frogs ．These sounds of the night now have a much deeper meaning ． 3. What does the text mainly talk about______________.DArthur Bonner works with the Palos V erdes blue butterfly(蝴蝶), once thought to have died out. Today the butterfly is coming back — thanks to him. But years ago if you‟d told him this was what he‟d be doing someday, he would have laughed, “You‟re crazy.” As a boy, he used to be “a little toughguy on the streets”. At age thirteen, he was caught by police stealing. At eighteen, he landed in prison for shooting a man.“I knew it had hurt my mom,” Bonner said after he got out of prison. “So I told myself I would not put my mom through that pain again.”One day he met Professor Mattoni, who was working to rebuild the habitat(栖息地) for an endangered butterfly called El Segundo blue.“I saw the sign …Butterfly Habitat‟ and asked, …How can you have a habitat when the butterflies can just fly away?‟” Bonner recalls. “Dr. Mattoni laughed and handed me a magnifying glass (放大镜), …Look at the leaves.‟ I could see all these caterpillars(蝴蝶的幼虫) on the plant. Dr Mattoni explained, …Without the plant, there are no butterflies.‟”Weeks later, Bonner received a call from Dr. Mattoni, who told him there was a butterfly needed help. That was how he met the Palos Verdes blue. Since t hen he‟s been working for four years to help bring the butterfly back. He grows astragalus, the only plant the butterfly eats. He collects butterflies and brings them into a lab to lay eggs. Then he puts new butterflies into the habitat.The butterfly‟s po pulation, once almost zero, is now up to 900. For their work, Bonner and Dr. Mattoni received lots of awards. But for Bonner, he earned something more: he turned his life around. For six years now Bonner has kept his promise to stay out of prison. While he‟s bringing back the Palos Verdes blue, the butterfly has helped bring him back, too.4. Which of the following would be the best title for the text?A. A Promise to MomB. A Man Saved by ButterfliesC. A Story of ButterfliesD. A Job Offered by Dr. Mattoni(设计思想: 学生通过更多的训练，进一步掌握如何抓住文章主要内容，掌握这一阅读微技能。