Unit 5 A delicate world Using Language 教学设计-2022-2023学年高中英语外研版（2019）选择性必修第二册

Unit 5 Section B Using Language 教学设计 科目：英语 课题：Section B Using Language 课时：1课时 教学目标与核心素养： 1.掌握本课时的重点单词 dissolve、nutrient、worm 和短语be native to、due to、rely on、feed on、prey on、breakdown、 take in、 be in existence、 depend on、 be responsiblefor、contribute to的用法，并能在真实语境中灵活运用。 2.掌握it 作形式宾语的用法。 3.引导学生关注话题的语用功能，学会表达质疑和回应别人的质疑。 4.了解食物链中生物的相互制约、相互依存，共生共荣及生态平衡的重要性。人类可以通过自己的努力保护各个生态系统，促进生态平衡；人类也能够为了自身的眼前利益掠夺资源，破坏生态平衡。人类不能超自然而存在，保护生态平衡也是保护人类自己，一旦生态平衡遭到破坏，危及整个生物圈，人类自身也在劫难逃。 教学重难点 重点： it作形式宾语的用法。 难点： 1.it作形式宾语的用法。 2.食物链使所有的生物保持着“一物治一物”的状态，只要没有外界的破坏，食物链就永远不会断，生态因食物链的存在而得到平衡。 课前准备：多媒体，黑板，粉笔 教学过程： 一、Pre-class 1. Greeting 学生活动：完成活动1。Look at the sentences and answer the questions. Sentence (a) and (c) are from the reading passage. a No visitor would think it surprising that the island is a UNESCO World Heritage Site. b No visitor would think that the island being a UNESCO World Heritage Site is surprising. c Experts felt it necessary to come up with a plan to remove all the rabbits from the island. d Experts felt to come up with a plan to remove all the rabbits from the island was necessary. • What does "it" refer to in sentences (a) and (c)? • What is the difference between the sentences in each group? Suggested answers: • "It" in sentence (a) refers to “the island is a UNESCO World Heritage Site". "It" in sentence (c) refers to "to come up with a plan to remove all the rabbits from the island". • When the object of a sentence is a that-clause (b) or an infinitive (d), we sometimes use "it" as an empty object and put the real object later to keep balance. For example, sentence (a) uses "it" as the empty object of “think", referring to the real object: "the island is a UNESCO World Heritage Site". Sentence (b) uses that-clause as the object of "think". 2、 While-class it 作形式宾语 当动词不定式（短语）、v-ing(短语）或从句作宾语时，为了保持句子结构的平衡，常用it作形式宾语，而将真正的宾语后置。此时的it无词义。其用法如下： （1）常以it作形式宾语的动词有：feel, consider, find, believe, make, take, imagine, prove, think, suppose, regard, notice等。 D find it easy to get on wi