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课件网) Reading Unit 7 The natural world Learning aims 通过阅读，了解三大主要生态系统 能正确运用本课时的重点词汇 Lead in What do you know about oceans, wetlands and forests Know about the three ecosystems by reading Activity 1 Prediction 1. What is the article about It’s about the three main ecosystems on earth—oceans, wetlands and forests. 2. What can you see in the pictures Picture 1: I can see dolphins and the ocean. Picture 2: I can see birds and a wetland. Picture 3: I can see trees and a forest. 3. What type of text is the article It’s an expository text. Scanning Listen to the article and analyse its structure. Main ideas Paragraph(s) What is an ecosystem (1) _____ What are the three main ecosystems (2) _____ How important are the ecosystems (3) _____ 1 2–4 5 A Look at the picture and choose the correct descriptions for each ecosystem according to the article. Write the correct letters in the boxes. a Cover 71% of the earth's surface b Cover nearly a third of the earth’s land area c Help clean the water d Help make the air clean e Help prevent floods f Produce about 70% of the earth's oxygen g The “heart” of the earth h The ”lungs“ of the earth i The “kidneys” of the earth b, d, h a, f, g c, e, i Careful reading Paragraph 1 Read the following sentences. Write a T if a sentence is true or an F if it is false. Then correct the false one(s). _____ 1. An ecosystem includes only living things in an area. _____ 2. Ecosystems are always large, like grasslands or oceans. _____ 3. Every ecosystem has a special role and helps keep the planet balanced. F F T all the living and non-living things in an area. can be of different sizes. Paragraph 2–4 E c o s y s t e m s The ocean— the “ (1) _____” of the earth · (2) _____ around 70% of the earth’s oxygen · Support the water cycle Wetlands— the “ (3) _____” of the earth Forests— the “ (6) _____” of the earth · Be home to around 40% of all the types of plants and animals · Help (4) _____ pollution and make the water clean · Help prevent floods by (5) _____ like huge sponges · (7) _____ carbon dioxide and produce oxygen · (8) ___ harmful things and help clean the air heart Produces get rid of kidneys storing water lungs Take in Trap Paragraph 5 What does each of these ecosystems support Each of them supports millions of plants and animals. Read the article again. Choose the correct answers to the questions. 1 What is an ecosystem made up of a Oceans, wetlands and forests. b Plants and animals. c Living and non-living things. 2 Why is the ocean the largest ecosystem of the three a It holds plenty of the earth’s water. b It makes up about 71% of the earth’s surface. c It is home to many kinds of plants and animals. 3 What do wetlands do during heavy rains a They make the water clean. b They hold water. c They get rid of water. 4 “They also trap harmful things in their leaves and help clean the air.” Which word can we use ... ...
