学案】2014-2015学年高中英语（人教版，选修6）同步检测：Unit++3+A+healthy+life第四学时.ppt

Unit 3　A healthy life　　　　　　　　　　　 　　　　　 第四学时　Grammar;it的用法(Ⅰ);1．人称代词it;“o was that at the door？” “It wWhas a man selling house insurance.” (it 指代a man selling house insurance) “门口的那个人是谁？” “销售住房保险的。”;2．非人称代词it;3．先行代词it;It is no use crying over spilt milk. (谚语) 覆水难收。 Its been a lot of fun meeting you. 见到你真是太高兴了。 (3)it代表that或wh-词引导的主语从句。 Has it been decided when we are to hold the sports meeting? 我们什么时候举行运动会决定了吗？;It is very important that he should go to the school of Art. 他应该上艺术学校是非常重要的。 It is a mystery to me how it all happened. 这一切是如何发生的对我来说是个谜。 (4)it代表不定式充当形式宾语。 Many people now make it a rule to buy cards for their friends before Christmas.;现在许多人已形成习惯在圣诞节前为朋友购买贺卡。 (5)it代表动名词充当形式宾语。 I think it a waste of time talking to him. 我认为与他谈话是浪费时间。