<例句>
It was you who had been wrong.
錯的是你。
<語法分析>
it 強調句子的主語，可用 who 或 that 引導句子的後面部分。用於強調的 it，可以對句子的某一處成分加以強調。例如可以強調句子的主語、賓語以及狀語等。It 的用法有很多，它最基本的用法是作代詞，主要代表剛提到的事物以避免重複，也可以代表某些抽象事物或代表一個彼此都知其何所指的東西。有時也可以不指具體的。東西，例如天氣、環境和時間等。先行詞的it 主要作為句子的形式主語，從而使句子變得平穩。
<觸類旁通>
(1) It was a great surprise to me when she did a thing like that.
她做這樣的事情我大為吃驚。
語法分析：It代表抽象的事物。
(2) Where does it hurt?
哪兒疼？
語法分析：it代表一個彼此都知其何所指的東西。
(3) How fat is it to Beijing?
到北京有多遠？
語法分析：it代表距離。
(4) It was she who lent us the money.
是她借錢給我們的。
語法分析：it用於強調句中，強調句子的主語。
(5) It's beyond me to say why.
我無法説個究竟。
語法分析：It作先行詞，作句子的形式主語，有平穩句子的作用，句子謂語有這幾種：be +形容詞或名詞，介詞短語+不定式，及物動詞+賓語+不定式。
<鞏固練習>
1. _____ says here there was a big fire in the city.
2. “Why, ____ is you!” she cried.
3. _____ takes two to make a quarrel.
4. Why is _____ that everyone thinks I'm narrow-minded?
5. Was _____ you that broke the window?
6. Does _____ itch much?
<參考答案>
1. It 2. it 3. It 4. it 5. it 6. it
it的用法1：用it作人稱代詞，可替代無生命的東西或事情，在性別不詳或無所謂時，也可指代人，尤其是指嬰兒。
it的用法2：it作主語時，可指自然現象、季節、時間、距離、環境等。
it的用法3：it可以作先行詞，用於強調句型中，強調主語、賓語、時間狀語、地點狀語、介詞賓語或從句等，強調句型中的it一般指已發生過的事，而不指尚未發生或提及的事。
it的用法4：it還常用作形式主語或形式賓語，代替較長的真實主語或真實賓語(其形式多為動詞不定式短語或that從句等)。
it的用法5：it可以代替前面提到的某個名詞、代詞或句子，但在believe, expect, forget, imagine , remember, think等詞後常常省略。
1. Beauty is an attitude. It has nothing to do with age.
美是一種態度，與年齡無關。
2. English has hurt me a thousand times, but I still regard it as my first love.
英語傷我千百遍，我待英語如初戀。
3. Success is not guaranteed. It is not handed to you. Success is earned.
成功無法保證，並非唾手可得。成功必須靠自己去爭取。
4. Success is not final, failure is not fatal: it is the courage to continue that counts.--Winston Churchill
成功不是終點，失敗也並非末日，最重要的是繼續前進的勇氣。
5. If you're not satisfied with the life you're living, don't just complain. Do something about it.
對於現況的不滿，不能只是抱怨，要有勇氣作出改變。
6. Good luck is when an opportunity comes along and you're prepared for it.
好運就是當機會來臨時，你早已做好了準備。
7. It's not about making the amazing saves. It's the little things and small things that made great gatekeepers great.
偉大的門將不是靠神奇的撲救成就，而是靠注重小事和細節成功。(Tim Howard美國國家隊門將)
8. Friendship means understanding, not agreement. It means forgiveness, not means（） the memories last, even if contact is lost.
友情是理解，不是妥協；是原諒，不是遺忘。即使不聯繫，感情依然在。
9. Remember, happiness doesn't depend upon who you are or what you have; itdepends solely upon what you think.--Dale Carnegie
請記住，幸福不在於你是誰或者你擁有什麼，而僅僅取決於你的心態！
10. It was just then that I chanced to look round.
就在那時，我恰好環顧了下四周。
11. I know it's nothing serious and I feel quite unemotional about it.
我知道那根本沒什麼大不了的，所以有些無動於衷。
12. The house seemed muted, hushed as if it had been deserted.
房子裏似乎悄然無聲，安靜得好像已經沒人在住一樣。
13. It was the uncommitted that Labour needed to reach.
工黨需要拉攏的是未表態者。
14. It had once been the home of a wealthy nobleman.
這裏曾是一個有錢貴族的宅邸。
15. I have $100m hidden away where no one will ever find it.
我把1億美元藏到了一個永遠沒人會找到的地方。
當不定式（短語）、動名詞（短語）或從句在某個句子中作賓語時，為保持句子結構平衡，避免句式結構的混亂，常用it作形式賓語，而將真正的賓語放在句尾，構成“動詞＋it＋賓語補足語＋不定式（動名詞或從句）”結構，也可稱作“6123結構”。此時it仍只起先行引導作用，本身無詞義。它可以代替三種形式：不定式、動名詞和賓語從句。
it作形式賓語時，需具備兩個條件： ① ② 足語，具備了這兩個條件，形式賓語it一定要用。
⒈ it代替不定式短語 think/ find/ feel/ consider/ make/ regard…+ it +形容詞/名詞 + 不定式短語 如：
①I find it pleasant to work with him.
(it 作形式賓語，代替不定式短語to work with him)
②They felt it difficult to finish the work in such a short time.
（ it 作形式賓語，代替不定式短語to finish the work in such a short time）
③She thinks it her duty to help us.
（ it 作形式賓語，代替不定式短語to help us）
④I think it my honor to be invited to speak here.
（ it 作形式賓語，代替不定式短語to be invited to speak here）
⑤Tom didn’t find it difficult to write letters in Chinese.
（ it 作形式賓語，代替不定式短語to write letters in Chinese）
⑥All these noises made it impossible for me to go on with the work.
（ it 作形式賓語，代替不定式短語to go on with the work）
⒉ it代替動名詞短語( 這隻限於少數句型，在多數情況下用不定式時更多一些)
如：
①The professor considers it no good reading without understanding.
②Do you consider it any good trying again
③He found it useless( no use) arguing with him.
④He thought it absolutely senseless attempting the impossible.
⑤I don’t think it worthwhile going to such a place.
⒊ it代替賓語從句：
如：
①We all thought it a pity that the conference should have been cancelled.
②I took it for granted that they were not coming.
③I’ll see to it that everything is ready in time.
“it”的特殊用法常出現在以下幾種結構中。
A. 動詞＋it＋when / if 從句。常見於appreciate, enjoy, like, dislike, love, hate, prefer等少數動詞之後。
We would much appreciate it if you could do us that favour.
I'd prefer it if I didn't have to finish the work.
B. 動詞+ it + that從句。常見於like, take, have, put等少數動詞之後（it相當於that從句的同位語）。
I take it that they will succeed sooner or later.
The newspapers have it that some Japanese firms have gone bankrupt.
Rumor has it that Mary is getting married.
I take it that you have been out.
Let me come and stay. You can put it that it was arranged before.
C. 動詞 + it + 介詞短語 + that從句。常見於bring it to one's attention; owe it to sb; take it for granted 等結構中。
I owe it to you that I finished my work in time.
Don't take it for granted that they will support you.
D. 動詞 + 介詞(短語) + it + that從句。常見於answer for, depend on, rely on, insist on, look to, see to, stick to 等結構中。
I'll see to it that everything is ready in time.
You may depend on it that Tom will help you with your English.
I’m counting on it that you will come.
E. 動詞+ it +過去分詞+從句。常見於幾個可以帶過去分詞作賓語補足語的動詞之後。
I heard it said that that factory was founded in 1995.
They haven't made it known where the meeting is to take place.
易混用其他句型
英語中有一些句型不含it, 但卻易被誤用了it，常見的有以下句型：
⒈ There is something/nothing wrong/ the matter with sb./ sth.
如：There is nothing wrong /the matter with him. He’s just pretending. 他沒什麼事，他只是在裝呢。
⒉ There is no doubt about…對…毫不懷疑
There is no doubt that…對…毫不懷疑
如：①There is no doubt about his suitability for the job. 毫無疑問，他適合這個工作。 ②There is no doubt about the fact. 關於這個事實毫無懷疑。
③There is no doubt that he is hard to deal with. 毫無置疑他很難對付。
⒊ There is no need (for sb.) to do sth.沒必要…
如：①There was no need for him to remain in Paris. 他沒有必要繼續留在巴黎。 ②There is no need for you to start yet. 你現在還不必動身。
⒋ There is no/a possibility that… …沒可能/有可能
(= It is impossible/possible that …)
如：①There is a possibility that the train may be late. 可能火車要晚點。
②There is no possibility that we’ll see him this weekend. 我們本週末不可能見到他。
⒌ There is a chance that …可能…
如：There is a chance that the sick child will get well. 這個生病的孩子可能會好起來的。
⒍ There be no/ some differences between…and……和…之間沒/有區別
如：There are some differences between the two languages. 這兩種語言之間有些區別。
⒎ After what seemed + 時間
如： After what seemed a very long time, the wounded soldier came back to life.
在經過似乎很長的一段時間之後，那個受傷的士兵甦醒了過來。
⒏ There be difficulty/ trouble (in) doing sth.幹…有困難
如：There was no difficulty in finding him. 找到他沒費什麼事。
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