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课件网) Unit 5 Lesson 28 The Study of Living Things 1.学习目标 3.重点探究 2.自主学习 学习导航 5.当堂检测 6.课堂总结 4.拓展提升 新课导入 Butterflies are beautiful, what do you know about them 学习目标 1.掌握单词：biology, butterfly, migrating, fantastic, grandchildren, female, chemical 掌握短语：draw one’s attention, return to…, as many as, lay eggs 2.了解并掌握定语从句的基本知识点 3.了解关于大自然生物的知识 自主学习 biology butterfly migrate fantastic completely grandchild female milkweed chemical puzzling n. 生物学；生物 n. 蝴蝶 v. 移居；迁徙 adj. 奇异的；了不起的;极好的 adv. 完全地 n. 孙子；孙女；外孙；外孙女 n. 雌性的动物或植物；女子 n. （植）马利筋 n. 化学物质 adj. 令人费解的 重点探究 Dr.Chip Taylor teaches biology at a university in the United States. He studies one kind of North American butterfly. Just like a migrating bird, this butterfly travels about 4000 kilometres south in fall.Fantastic facts about the butterfly have been drawing Dr.Taylor’s attention. In Mexico, the butterflies always return to the same small piece of forest, which is only 20 kilometres wide.Here,as many as 230 million butterflies spend the winter.They can cover some trees almost completely.The butterflies that return to the south are the great-great grandchildren of the butterflies that left for the north.When they begin to travel north in spring, the females lay eggs. They lay eggs on only one plant:milkweed. But in Mexico, people cut down the trees that the butterflies need to rest on beacause they want more land for farming. In the United States and Canada, farmers use chemicals that kill milkweed. This worries Dr.Tayor a lot. Now things are improving. Mexico has begun to protect parts of its forests. The United States and Canada have encouraged farmers to use less chemicals. Scientists still don’t understand how the butterflies know when to fly south. If they are even a few days late, they will freeze. And how do all the great-great grandchildren find the same forest in Mexico every year This is both puzzling and interesting for many scientists. There are many mysteries yet to be discovered by those interested in science. Would you like to study biology 1 Read the lesson and complete the table. Fantastic facts about butterflies The butterflies always_____to the same small piece of forest and_____the winter there.The butterflies that return to the south are the great-great grandchildren of the butterflies that left for the north.The females _____eggs on only one plant:milkweed. Things that Dr.taylor worries about In Mexico, people cut down the trees that the butterflies need to _____on.In the U.S. and Canada,farmers use chemicals that _____milkweed. Things that scientists can’t understand How do the butterflies know when to fly south How do the great—great grandchildren of the butterflies _____the same forest return spend lay rest kill find Let's Do It! Attributive clause 1)who, whom, that Is he the ... ...
