英文It的用法

英文It的用法 词语外，另一个特点是它后面的内容都是表示天 （一）作人称代词 气、时间、距离、度量衡及情况等。 1、it代替前面（或后面）的单数名词或分句等所 It is fine (rainy, windy, etc.). 表示的事物。 It is noon. e.g. You cannot eat your cake but have it. It is a half hour’s walk to the factory. （it代替前面的cake） It is eighteen square metres in area. Although we cannot see it, there is air all What does it matter? around us. （it代替后面的air） （三）作强调词，构成强调结构 They say he has left town, but I don’t believe 用以帮助改变句子结构，使句子的某一成分受到 it. （it代替前面They„town分句中的情况） 强调。 2、代替有生命但不能或不必分阴阳性的东西（包（1）强调句句型 括婴儿）。 1、陈述句的强调句型：It is/ was + 被强调部e.g. Yesterday we saw a big tree. It was fully 分（通常是主语、宾语或状语）+ that/ who（当twenty metres high. （it代替前面的tree） 强调主语且主语指人）+ 其它部分。 The baby cried because it was hungry. （it e.g. It was yesterday that he met Li Ping. 代替前面的baby） 2、一般疑问句的强调句型：同上，只是把is/ was 3、在某些习惯说法中，可以代替人。 提到it前面。 e.g. ---- Someone is knocking at the door, e.g. Was it yesterday that he met Li Ping? Peter. ---- Who is it? ---- It’s me. 3、特殊疑问句的强调句型：被强调部分（通常是 ---- Who are singing? ---- It is the 疑问代词或疑问副词）+ is/ was + it + that/ who children. + 其它部分？ ---- The light is still on in the lab. It must e.g. When and where was it that you were born? be the third-year students doing the 4、强调句例句：针对I met Li Ming at the railway experiment. station yesterday.句子进行强调。 4、it与one的区别：这两个词都可以代表前面说 强调主语：It was I that (who) met Li Ming at 过的名词，但it用于同名同物的场合；one则用于the railway station yesterday. 同名异物的场合。 强调宾语：It was Li Ming that I met at the e.g. ---- Do you still have the bicycle? ---- railway station yesterday. No, I have sold it. 强调地点状语：It was at the railway station ---- Is this knife yours? ---- No. It is that I met Li Ming yesterday. Xiao Zhang’s. Mine is the one on the desk. 强调时间状语：It was yesterday that I met Li 5、it与that的区别：两词都可代替某一特定名Ming at the railway station. 词，但that指同一类，并非同一个。 5、注意：构成强调句的it本身没有词义；强调 e.g. The climate of South China is mild（温句中的连接词一般只用that, who，即使在强调时和的）; I like it very much.（it指the climate 间状语和地点状语时也如此，that, who不可省略；of South China） 强调句中的时态只用两种，一般现在时和一般过去 The climate of South China is much better 时。原句谓语动词是一般过去时、过去完 than that of Japan.（that指the climate） 成时和过去进行时，用It was „ ，其余的时态用（二）作无人称代词 It is „ 。 it作无人称代词时，除了句中找不到它所代表的（2）not „ until „ 句型的强调句 1、句型为：It is/ was not until + 被强调部 分 + that + 其它部分 e.g. 普通句：He didn’t go to bed until/ till his wife came back. 强调句：It was not until his wife came back 练习It的用法 that he went to bed. 1. My bike is missing. I can’t find ____ 2、注意：此句型只用until，不用till。但如果 anywhere. 不是强调句型，till, until可通用；因为句型中 It is/ was not „ 已经是否定句了，that后面的 A. one B. ones C. it D. that 从句要用肯定句，切勿再用否定句了。 2. ---- Who’s that? ---- ____ Professor Li. （3）谓语动词的强调 A. That’s B. It’s C. He’s D. This’ 1、It is/ was „ that „ 结构不能强调谓语， 如果需要强调谓语时，用助动词do/ does或did。 s e.g. Do sit down. 务必请坐。 3. ____ was Jane that I saw in the library this He did write to you last week. 上周他确实 morning. 给你写了信。 A. It B. He C. She D. That Do be careful when you cross the street. 过 马路时，务必（千万）要小心啊！ 4. ---- Have you ever seen a whale alive? ---- 2、注意：此种强调只用do/ does和did ，没有Yes, I’ve seen ____. 别的形式；过去时用did ，后面的谓语动词用原形。 A. that B. it C. such D. one 其它成分。”在这个句型中，it本身没有词义。 5. The color of my coat is different from ____ （四）引导词it作形式主语（宾语） of yours. 为了使句子平衡，常采用形式主语（或宾语）it ， A. this B. that C. it D. one 而把真正的主语（或宾语）置于句子后面。通常引 导词it与它所代替的句子成分中间要夹有某些词。 6. ____ will do you good to do some exercise 例： every morning. It takes half an hour to go there on foot. A. It B. There C. Those D. You （It是形式主语，真主语是to go there on foot） 7. We think ____ our duty to pay taxes to our We thought it strange that Mr Smith did not come last night. （it在句子中为宾语，strangegovernment. 为宾语it的补助语，真宾语是that从句。） A. that B. this C. its D. it 但有时it与所替代部分之间并不夹有其它词。 8. The climate of Shanghai is better than ____ 例： You may depend on it that they will support of Nanjing. you.（因为介词on之后一般不直接接that引导的 A. that B. it C. which D. what 宾语从句。注意：it不是多余的，不能当作错句） 9. ____ four years since I joined the Army. A. There was B. There is C. It was D. It is 三、省略 10. How long ____ to finish the work? 为了使讲话和行文简洁，句中某些成分有时可省 A. you’ll take B. you’ll take it C. will 略。省略可分以下几种情况： it take you D. will take you （一）简单句中的省略 11. It was through Xiao Li ____ I got to know 1、省略主语：祈使句中主语通常省略。其它省略 Xiao Wang. 主语多限于少数现成的说法。 A. who B. whom C. how D. that e.g. (I) Thank you for your help.（括号内为12. It was in the rice fields ____ we had our 省略的词语，下同） league meeting. (I) see you tomorrow. (It) Doesn’t matter. A. where B. that C. in which D. on which 2、省略主谓语或主谓语的一部分。 13. It was on October 1st ____ new China was e.g. (There is) No smoking. (Is there) founded. Anything wrong? Why (do you) not say hello to A. which B. when C. as D. that him? 14. Was it because he was ill ____ he asked for 3、省略作宾语的不定式短语，只保留to。 leave? e.g. ---- Are you going there? ---- I’d like A. and B. that C. that’s D. so to (go there). 15. Mary speaks in a low voice; ____ is He did not give me the chance, though he had difficult to know what she is saying. promised to (give me the chance). A. it B. that C. so D. she 注意：如果该宾语是be动词或完成时态，则须在16. It was ____ I met Mr Green in Shanghai. to之后加上be或have。 A. many years that B. many years before C. e.g. ---- Are you an engineer? ---- No, but many years ago that D. many years when I want to be. 17. ____ is not everybody ____ can draw so well. ---- He hasn’t finished the task yet. ---- A. It, all B. It, that C. There, who D. Well, he ought to have. There, that 4、省略表语。 18. So ____ that no fish can live in it. e.g. ---- Are you thirsty? ---- Yes, I am A. shallow is the lake B. the lake is (thirsty). shallow C. shallow the lake is D. is the lake 5、同时省略几个成分。 shallow e.g. Let’s meet at the same place as (we met) yesterday. ---- Have you finished your work? ---- (I have) Not (finished my work) yet. 2、不定式符号to的省略 （二）并列句中的省略 ?、并列的不定式可省去后面的to。 两个并列分句中，后一个分句常省略与前一分句 e.g. I told him to sit down and wait for a 中相同的部分。 moment. e.g. My father is a doctor and my mother (is) ?、某些使役动词（如let, make, have）及感官a nurse. 动词（如see, watch, notice, hear, feel, look I study at college and my sister (studies) at和listen to等）后面作宾语补足的不定式一定 at high school. 要省去to，但在被动语态中须把to复原。 （三）主从复合句中的省略 e.g. ---- I saw the boy fall from the 1、主句中有一些成分被省略。 tree. ---- The boy was seen to fall from the e.g. (I’m) Sorry to hear that you are ill. tree. (It is a) Pity that he missed such a good ?、介词but前若有动词do，后面的不定式不带chance. to。 2、省略了一个从句或从句的一部分，用so或note.g. The boy did nothing but play. （切不可用it或that）代替。 3、在某些状语从句中，从句的主语与主句主语一 e.g. ---- Is he coming back tonight? ---- 致时，可省去“主语 + be”部分。（参看“状语I think so. 从句”有关部分） ---- Is he feeling better today? ---- I’4、连词if在部分虚拟条件句中可省略，但后面的 m afraid not. 语序有变化（参见“倒装句”有关部分） 这种用法常见的有：How so? Why so? Is that so? 5、主句与从句各有一些成分省略。 I hope so. He said so 及I suppose not. I e.g. The sooner (you do it), the better (it will believed not. I hope not等。（但I don’t think be). so比I think not更常用）。 四、插入语 （四）其它省略 英语句子中（尤其在口语中）常插入一些单词、 1、连词that的省略： 短语或者句子，用来补充某些含义。语法上称他们 ?、宾语从句中常省略连词that，但也有不能省略为“插入语”。 的情况（参看“名词性从句”等有关部分）。 （一）插入语的类型： ?、在定语从句中，that在从句中作宾语时可省 1、单词（多是副词），如：besides, however, 略。 otherwise, therefore, though等。 ?、引导主语从句、同位语从句等的连词that一 e.g. She is looking fit, though. 他看起来倒般不可省略。在表语从句中偶尔可省略。 是健康。 I can, however, discuss this when I see you. e.g. You know that I think you are wrong. 我 2、短语 认为，你明白你错了。 e.g. China and India, for example, are What on earth do you mean? 你究竟是什么意neighbours. 思？ By the way, where are you from? （三）插入语在句中的作用 3、句子 一般来说，插入语在句中不起主要作用。如果把 e.g. He is an honest man, I believe. 插入语抽去，句子的含义不大受影响。但是，有的 Jack, as far as I know, isn’t clever. 插入语却是句子不可缺少的一部分。 （二）插入语的位置 e.g. He got the news from nobody knows where. 通常插入语位于句中，并用逗号隔开。但有时，他这消息谁也不知道是从哪儿得来的。 也可位于句首或句末（见上面例句）。也有时，并（四）插入语的特殊用法 不用逗号隔开。 下面这种复杂的特殊疑问句，也