Unit4Globalwarming课件3（人教版选修6）.ppt

;it的用法(Ⅱ) 一、it的用法;it的用法;it的用法;it的用法;it的用法;二、强调句的判断 若去掉句子中的It is/was和that后，适当调整语序或不调整语序，意义基本不变且语法结构完整，就是强调句型。否则就不是强调句。试比较： It is for three hours that they have worked.(强调句型) 他们已经工作三个小时了。 It is a wonder that he is still alive.(it作形式主语句型) 他仍然活着真是个奇迹。 It is the best book that I have ever read.(it代指书) 这是我看过的最好的书。;温馨提示：①it后面的动词be常用两种形式：is与was。如果原句中的谓语动词是现在或将来各种时态，用“It is...that...”，如果原句中谓语动词是过去某个时态，则用“It was...that...”。 ②对名词性从句引导词强调的句式是“引导词＋it is/was＋that＋句子其余部分”。 The question is whom it is that we can turn to for help.问题是我们到底可以向谁求助。;③“It is/was...that...”结构不能强调谓语，如需强调谓语时，肯定句中用助动词do/does或did。 Tom does study hard now. Tom现在学习非常努力。 ④这一句型通常不能用来强调由since，as，why，although，where等引导的从句。;Ⅰ.句型转换 1．Xiao Li met your sister in the zoo yesterday.(强调主语) 答案：It was Xiao Li who/that met your sister in the zoo yesterday. 2．Guo Yue is one of the best players in China.(强调状语) 答案：It is in China that Guo Yue is one of the best players.;3．We were doing our homework when the teacher came in.(强调时间状语) 答案：It was when the teacher came in that we were doing our homework. 4．I gave him a picture of Nash.(强调直接宾语) 答案：It was a picture of Nash that I gave him. 5．I didn’t realize the importance of learning English until I went to America.(强调状语) 答案：It was not until I went to America that I realized the importance of learning English.;6．He didn’t go to school because he was ill.(强调原因状语) 答案：It was because he was ill that he didn’t go to school. 7．I came across Jay Chou in the park yesterday.(强调宾语) 答案：It was Jay Chou that I came across in the park yesterday. 8．He makes a living by selling vegetables.(强调谓语) 答案：He does make a living by selling vegetables. 9．Didn’t you go to bed until your father came back last night？(强调状语) 答案：Wasn’t it until your father came back last night that you went to bed?; 10．I am working now.(强调主语) 答案：It is I who am working now.;Ⅱ.单项填空 1．______ that caused him to serve dinner an hour later than usual. A．It was we being late B．It was our being late C．It was we were too late D．It was because w