Unit 4 Global Warming Period3 GrammarLearning aims: 1. Review the use of “it” 2. Learn useful “it” structuresImportant point: Learn emphatic sentence.Difficult point: Master the use of” it”.使用说明及学法指导：1. 通过自学同步检测 P，完成预习案。2. 完成时间：30 分钟。预习案 Previewing CaseTask 1 写出“it”在句中指的内容。1) Guangzhou is a beautiful city, isn’t it? ( )2）You’ve helped me a lot; I’ll never forget it. ( )3）— What’s this? — It’s a computer. ( )4）— Whose book is that? — It's hers． ( )5）It’s time for lunch．( )6）It’s raining hard．( )7）It’s two miles from the school to our home．( )8）It is easy to buy a new radio. ( )9）It is no use telling him that. ( )10) It is exciting that we can do what we like to do. ( )11) I feel it my duty to help him. ( )小结： it 可以代替______ ,______和上文的_____；it 可以指时间，_______, ______，环境，度量等；it 作形式_____或_____代替动词不定式，动名词和从句。Task 2 it 替代 to do 作形式主语或宾语1) It takes sb. ... to do sth. 做．．．要花费某人修建长城花了成千上万的人力和大量的时间。___________________________________________________________________to build the Great Wall.2)It is adj+ (kind，bad , brave ,careless, clever, cruel, foolish ,stupid ,wise ,wrong等形容逻辑主语特征) of sb to do sth.你重复相同的错误真的很笨。______________________________________________________________3）It is adj /n + for sb. to do sth. 常用形容词：important, necessary, natural, easy, safe, common, normal ,hard, difficult ,dangerous 等；名词：idea, habit, pity, shame, time, surprise, wonder 等彼此帮助对我们来说非常重要。___________________________________________________________去野炊是一个好想法。____________________________________________________________________4) think\believe\make\find\consider\feel 等+it + adj\n (for/of...
