高二年级英语 选修六第三单元学案-The use of “it”【目标解读】1. to learn the use of it in different situations 2. to learn to identify and use it in the exercise. 【自主观察并学习it的用法】 想一想 it指代什么？1Who is knocking at the door?Its me. _2My dictionary is missing. I cant find it anywhere. _3It was time to quit smoking. _4It is 10 kilometers to the castle. _5Whats this?Its a computer. _6It is no good crying over spilt milk. _7He found it difficult to accustom himself to getting up early. _8It is only when the disease has progressed to AIDS that a person begins to look sick. _我的发现 1)it用作人称代词，代替上文提到的 或 。(如例句1和2)2)it用作非人称代词，不指具体的东西，而是泛指 、 、 、温度、 等。(如例句3和4)3)it在答语中可代替指示代词 或that。(如例句5)4)it用作形式主语或形式宾语，代替 、 或从句。(如例句6和7)5)it用来构成 等各种句型。(如例句8)学一学 一、作人称代词1用于代替上文提到过的事物或整个句子所表述的事实 Dont blame me. Its not my idea. 不要责备我，不是我的主意。 This little dog is very lovely. It belongs to my neighbour. 那只小狗很可爱，是我邻居的。2用于指代人 1)指代说话者心目中不太清楚的那个人，常在打电话或敲门时用。 -Whos knocking at the door?谁在敲门？ -It must be my brother.一定是我弟弟。2) 指代性别不详的婴幼儿或在不计较性别时，也可用it来指人。 The baby is crying; maybe its hungry.那婴儿在哭，估计是饿了。3用于代替指示代词this和that： -Whose dictionary is that? -Its mine.即学即练 你不能吃蛋糕，那是我的。You cant eat the cake and _汤姆考试没及格。你听说了吗？Tom has failed in the exam. _.谁制造的噪音？-Who is making such a noise?一定是那些孩子。-_这小孩一见到母亲就笑了。The baby smiled when _二、作非人称代词 it有时并不指具体的东西，而泛指天气、时间、日期、距离、价值、度量、温度、环境等，称为非人称代词it。1. It was 12 oclock but he hadnt turned up.12点了，他却还没有露面。2. Is it still raining? 还在下雨吗？3. Its over 200 miles from London to Manchester.从伦敦到曼彻斯特有200多英里。即学即练 写出下面it指代的内容It was 12 oclock when they came out of the hall. Its damp and cold. I think its going to rain. Itll be lovely in the garden tonight. How far is it from your office to the bank？ 三作形式主语 当动词不定式、动名词或从句作主语时，通常把它们置于句末作真正的主语，而使用it作形式主语。1代替动词不定式 常用句型为：1) It beadj.of sb. to do sth.该句型中的不定式短语是真正主语，如果不定式的逻辑主语由of引起，句中的形容词必须是表示逻辑主语特征的形容词(即句中的形容词是修饰逻辑主语的)。此类形容词为描写人的，有bad, brave, careless, clever, cruel, foolish, good (好心的), honest, horrible, kind, lazy, modest, naughty, nice, polite, rude, silly, stupid, wise, wrong等。Its clever of you to do like this.你这样做很聪明。2) It beadj.for sb. to do sth.该句型与上一个同属一个句型。不定式的逻辑主语由for引起，形容词常表示重要性，紧迫性，频繁程度，难易，安全等情况(即句中的形容词是修饰动词不定式的)。常见的形容词有important, necessary, natural, easy, safe, common, normal, hard, difficult, dangerous, unusual, impossible, pleasant等。It is necessary for older people to understand what they think and feel. 年长的人有必要了解他们在想些什么，他们有什么感觉。3) It takes sb. some time to do sth.做某事要花费某人一段时间。eg.It took me three hours to finish the work. 我花了三个小时才做完这项工作。4) It beadj.to do sth. It is important to master a foreign language. 掌握一门外语很重要。2代替动名词 常用句型为： Its useless/(of) no use/(of)no good doing sth.该句型常译为“做也是徒然的/没有益处的”，句中的动名词短语是真正的主语，表语可以是no/any/much/great use/good/fun/pleasure等。It is no use going there so early. 这么早去那里没有用。3代替主语从句 常用句型为：1)It be形容词(clear, possible, obvious, certain, difficult, likely, .)主语从句。It is uncertain whether he can come to Marys birthday party or not. 他能否参加玛丽的生日聚会还不确定。2)It is/was形容词(necessary/natural/strange/important.)主语从句(虚拟should do/be done) It is strange that the Japanese Team should win the match.3)It is/wasv.ed(said/reported/thought/believed/hoped/known)主语从句(主+谓+) =主+ is/wasv.ed(said/reported/thought/believed/hoped/known)+ to + 谓(原形) +1. It is reported that 16 people were killed in the accident.=_2. It was said that there was nothing left after the great fire. =_3) It is/was名词(a pity/a shame/a surprise/an honour)主语从句(虚拟should do/be done)It is a pity that such a thing ( should ) happen in your class. 4) It happens /seems/looks/appears/occurs to sb.that + 从句 (主+谓+)=主+ happens /seems/looks/appears + to + 谓(原形) +It seems that there is no way out of our difficulty. 似乎我们无法摆脱困难了。=_即学即练1.完成句子跟他争论这件事是没有用的。_ the matter with him.奇怪的是你竟然能在如此短的时间内完成如此艰巨的任务。_ you _such a hard task in such a short time.2.句型转换 That he doesnt like it is very clear. _he doesnt like it.It is said that he has gone abroad._ abroad.Its important that she (should) come to the party. come to the party.He happened to be working at that time. It happened that at that time.四、作形式宾语1用于“主语及物动词宾语宾语补足语”句型中：当复合宾语中的宾语是不定式、动名词或宾语从句时，常使用it作形式宾语，而往往把真正的宾语不定式、动名词或宾语从句