2012届人教新课标高中总复习(第1轮)英语课件：part2第13讲it的用法及强调句型.pptVIP

* * it的用法 一、it作指示代词 【完成句子】 用one，ones，it，that，those填空 (1) — I cant find my watch. 　 — You havent found ______？ If you want to buy a new ______， I suggest you buy ______ made in China. (2) Weve got a big cup and two small ______. (3) The weight of an elephant is much greater than ______ of a tiger. (4) The books on the first shelf are easier than ______ on the second shelf. (5) The boy told his story and ______ of the girl upstairs. 【答案】 (1) it; one; one　 (2) ones　 (3) that (4) those / the ones (5) that / the one 【结论1】 ①指代上文提过的事物时，it指的是同名同物，相当于the＋名词； ②one指的是同名异物，表示单数可数名词相当于a ＋名词；a / an＋形容词＋one等于a / an＋形容词＋名词；复数形式用ones； ③that后面常有后置定语，有特指意义，代替不可数名词或单数可数名词，相当于the＋名词； ④复数名词用those，相当于the ones。 【例句观察】 — Someone is knocking at the door. Who is it? — It must be Leo. He said hed come to see me. 【结论2】it指代人时，常指小孩或身份不明的人。 【例句观察】 Its too quiet in the room. Everyone just keeps silent. 【结论2】it可用以指代环境或情况。 【完成例句】 根据语境补全句子 (6)— What time is it now? — Its half past seven. (7)— It is spring now and its warm these days. 【结论4】 it可用以指代时间、季节、天气或距离。 【注意】 it指代时间时，有如下一些句型： (1) It is time for sth. (for sb.)to do sth. / that－从句(should do / did, 必须用虚拟语气) 例： ① Its time for lunch. ② Its time for us to clean the house. ③ Its time that we should clean the house. ＝Its time that we cleaned the house. (2) It is / has been ＋ some time ＋ since－从句 (从句用一般过去时) (3) It / This is the first / second…time that－从句(必须使用现在完成时) 这是某人第……次做了某事。 It / That was the first / second…time that－从句(必须使用过去完成时) 例：①It is the second time that she has visited the Great Wall. 　 ②This was the first time that I had come late to school. (4) It was ＋时间点 ＋ when －从句 例： It was evening when we got home. 　 ＝It was evening in which we got home. (5) It was / will be ＋ some time ＋ before －从句 例：①过了5年他们才从北大毕业。 It was five years before they finally graduated from