牛津譯林版高中英語必修五unit 3《science and nature》（第4課時）教案-文庫吧
2024-11-15 15:07 本頁面
【正文】 s that never existed before. While many people are excited about these n ew technologies, these same technologies frighten others. Nowhere is this truer than with geically modified (GM) food. There are two ways in which a plant or an animal can be geically modified. First, new material can be inserted into its DNA to give the plant or animal qualities which it would never have in nature. Second, material can be taken from the DNA of a plant or an animal in order to remove qualities which are not desired. One aim of GM research is to produce food which will make us healthier. So far, this technology has been used to produce plants which are better able to defend themselves against pests and disease. Supporters of GM food argue that GM plants are healthier and have larger harvests. While there has been research in GM animals such as pigs, no GM meat is being sold at present. Many questions have been raised about GM food. No one really knows whether it is safe for animals or humans to eat. Scientists admit that more tests should be done on GM food. Research has been limited to increasing production profits, rather than making sure that GM foods are safe. GM food could therefore be dangerous to eat. There is also a question as to whether GM plants are safe for the environment. Since GM crops are planted outside, they are part of the food chain— insects and other animals eat them or use their products, and these insects and animals will be eaten by yet other animals. No one knows what effects the GM material might have on the food chain. Since no one really knows whether GM food is safe, many countries have hesitated to give permission for the production of GM foods, as they would rather be cautious with this new technology. Step 1: Read and learn ◆ Listen to the text and grasp the general spirit of the text Language focus: ◆ 1. consider vt. 考慮；認為考慮；認為 知識探究： I’m considering changing my job. 我在考慮還份工作。 We’re considering selling the house. 我們正在考慮賣掉房子。 I consider what he said as reasonable. 我 認為他說的有道理。 She considers it impolite to talk while eating. 她認為吃飯的時候說話是不禮貌的。 He was generally considered to have invented the first puter. 人們普遍認為是他發(fā)明了第一臺計算機。 We consider Jack to have let out the secret. 我們認為是杰克泄露了秘密。 歸納整理： consider 作“考慮”講時 ,其后可接名詞、 代詞、動名詞或 賓語從句 ,也可接由how, what等引導的不定式 ,但不可直接接不定式。 consider + n. / pron. consider + doing. consider +從句 consider +疑問詞 +to do consider 為“認為”時 ,后接 that 從句 ,復合賓語或帶
教學課件相關推薦
鄂ICP備17016276號-1