?　　句型1
    It (so) happened(chanced) that +clause. = sb. happened /chanced to do sth. =sb.did sth.by chance. 如：
    It happened that he was out when I got there. 當(dāng)我到那兒時，碰巧他不在。=He happened to be out when I got there.= It chanced that he was out when I got there= He was out by chance when I got there.
    句型2
    It seems that sb. do/ be doing/ have done/ had done= Sb. seems to do/ be doing/ have done/to be done/to have been done(還有動詞appear等可這樣使用)如:
    It seemed that he had been to Beijing before.他好象以前去過北京。=He seemed to have been to Beijing before.
    句型3
    It is / was+被強(qiáng)調(diào)的部分+that(who)+剩余的部分.如：
    It wasn't until he came back that I went to bed.直到他回來我才睡覺。(一定要注意被強(qiáng)調(diào)句型中的謂語動詞否定的轉(zhuǎn)移)。 It was because he was ill that he didn't come to school today.只因?yàn)樗胁×私裉鞗]有來上學(xué)。(只能用because而不能用for, as 或since)
    It is I who am a student. 我確實(shí)是個學(xué)生。(句中am不能用are來代替。)
    句型4
    It is high time (time/ about time)+ (that) 主語+should do / did+其它。(從句中的謂語動詞用的是虛擬語氣。)如:
    It is high time that we should go / went home.我們該回家了。
    句型5
    It is / was said ( reported…)+that+從句. 如：
    It was said that he had read this novel.據(jù)說他讀過這篇小說。=He was said to have read this novel.
    句型6
    It is impossible / necessary/ strange…that clause.(從句中的謂語用should+do / should have done，其形式是虛擬語氣。)如：
    It is strange that he should have failed in this exam.真奇怪，他這次考試沒有及格。
    句型7
    It is + a pity/ a shame…that clause.(注意從句中的謂語動詞用should do或should have done的形式，但should可以省略。)如：
    He didn't come back until the film ended. It was a pity that he should have missed this film. 他直到電影結(jié)束才回來。他沒有看到這部電影真可惜。
    句型8
    It is suggested / ordered/ commanded /…that +clause.(從句的謂語動詞用should do, 但should可以省略。)如：
    It is suggested that the meeting should be put off.有人建議推遲會議。
    句型9
    It is/was+表示地點(diǎn)的名詞+where+從句。(注意本句不是強(qiáng)調(diào)句型，而是以where引導(dǎo)的定語從句。)如：
    It was this house where I was born.請比較：It was in this house that I was born.(后一句是強(qiáng)調(diào)句型。)
    句型10
    It is / was +表示時間的名詞+when+從句。(注意本句型也不是強(qiáng)調(diào)句型，而是以when引導(dǎo)的定語從句。)如：
    It was 1999 when he came back from the United States. 請比較：It was in 1999 that he cameback from the United States.
    句型11
    It is well-known that+從句。如：
    It is well-known that she is a learned woman.眾所周知，她是個知識淵博的婦女。
    句型12
    It is +段時間+since+主語+did. 請比較：
    It was +段時間+since+主語+had done. 如：
    It is five years since he left here.他已經(jīng)離開這兒五年了。
    It was five years since he left here.(同上)
    注意下列句型的翻譯:It is five years since he lived here.他從這兒搬走已經(jīng)有五年了。
    句型13
    It +謂語+段時間+before+主語+謂語.( before引導(dǎo)的是時間狀語從句。)　如：
    It wasn't long before the people in that country rose up.沒有多久那個國家的人民就起義了。
    It will be three hours before he comes back.三個小時之后他才能回來。
    句型14
    It is +形容詞(possible, impossible, necessary等) +for+ sb.+ to do. 如：
    It is impossible for me to finish this work before tomorrow.我明天之前完成此工作是不可能的。
    句型15
    It is +(心理品質(zhì)方面的)形容詞+of + sb. +to do.= 主語+ be +形容詞+to do.(常用的形容詞有：kind, stupid; foolish, good, wise等。)如：
    It is kind of you to help me.=You are kind to help me.你真好給我提供了幫助。
    句型16
    由as引導(dǎo)的非限定性的定語從句。如：
    As we have known, he is a most good student.眾所周知，他是個很好的學(xué)生。請比較：It is well-known that he is a most good student.(前一個是定語從句，而后者是個主語從句。)
    With fresh water, the world will be prosperous.
    高考英語