4. Was it in this palace           the last emperor died ?

A. that       B. in which          C. in where            D. which

〖答案與簡析〗選A。測試it 用在強(qiáng)調(diào)結(jié)構(gòu)中，為了強(qiáng)調(diào)句子的某一成分（通常是主語、賓語或狀語），常用強(qiáng)調(diào)It is (was) + 被強(qiáng)調(diào)成分 + that(或who）…。被強(qiáng)調(diào)部分指人時用 that 或 who ，在其它情況下（包括強(qiáng)調(diào)時間或地點狀語）用that 。又如：

1）Was it during the Second World War            he died ? (MET 88）

     A. that             B. which        C. in which            D. then

2) It was not            she took off her dark glasses            I realized  she was a famous film star .

     A. when ; that  B. Until ; that              C. until ; when       D.  when ; then

答案 1) A  2) B。

3. I don't think              possible to master a foreign language without much memory work .

A. this B. that   C. its     D. it

〖答案與簡析〗選D。測試 it 用作形式賓語，代替由不定式、動名詞或從句表示的真正賓語。當(dāng)賓語有自己的補(bǔ)足語時，用it作形式賓語，真正賓語放在補(bǔ)足語之后。常用這種句型的動詞有think , make ,  find , feel , consider 等。

2. Is               necessary to tell his father everything ?

     A. it         B. that            C. what         D. he

〖答案與簡析〗選A。測試 it 用作形式主語，代替由不定式（或不定式復(fù)合結(jié)構(gòu)）、動名詞或從句表示的真正主語。又如：

1）Is               possible to fly to the moon in a spaceship ?

     A. now            B. man           C. that            D. it

2）Is               necessary to complete the design before National Day ?

     A. this             B. that            C. he              D. it

3）Does           matter if he can't finish the job on time ?

     A. this             B. that            C. he              D. it

4）It worried a bit          her hair was turning grey .

     A. while          B. that            C. if D. for

答案1） ―  4）DDDB。

1. Tom's mother kept telling him that he should work harder , but           didn't help .

    A. he          B. which           C. she          D. it

〖答案與簡析〗選D。測試 it 用作人稱代詞，代替前文提到過的事物。又如：

1）― The light in the office is still on.

     ― Oh , I forgot            .

     A.  turning it off     B. turn it off     C. to turn it off    D. having turned it off

2）― Have you heard the news about Tom ?

  ― No , what          ?

     A. is it           B. it is          C. are they      D. they are

3）If you don't know the word , why don't you             in the dictionary ?

     A. look at it       B. look after it       C. look up it       D. look it up

答案1）― 3）CAD。值得注意的是，由動詞和副詞組成的短語動詞用it 作賓語時，it 應(yīng)置于動詞和副詞之間。

2. it 代替連接代詞或連接副詞引導(dǎo)的從句作形式主語。

1) It is  known (not decided , not made clear ,  found out ,  discussed , being discussed , being considered , a question , uncertain等) + 連接代詞或連接副詞引導(dǎo)的從句。

It is still a question when we shall have our sports meet . 我們將什么時候舉行運動會還是一個問題。

It is uncertain whether he can attend this conference or not . 他能否來開會還不能確定。

2) It doesn't matter(doesn't  matter too much , doesn't make too much difference等) + 連接代詞或連接副詞引導(dǎo)的從句。如：

It doesn't matter whether we go together or separately . 我們一起去還是分開去都可以。

It doesn't matter too much to me what you do or where you go . 你做什么或去什么地方，對我都無關(guān)緊要。

【動腦動手】

單元能力立體檢測

1. it 代替連詞 that 引導(dǎo)的從句作形式主語。

1) it + be + 過去分詞 + that 從句

It's said that Tom has come back from abroad . 據(jù)說湯姆已經(jīng)從國外回來了。

It was reported that dozens of  children died in the accident . 據(jù)報導(dǎo)，數(shù)十名兒童在事故中死亡。

可用于該句型的過去分詞還有：known , thought , told , believed , hoped , announced ,expected , decided , suggested等，該句型�？梢赞D(zhuǎn)換成含有賓語從句的復(fù)合句或者含有不定式作主補(bǔ)的簡單句。如：

 It's said that Tom has come back from abroad . →People say that Tom has come back from abroad . →He is said to have come back from abroad .

2) It + be + 名詞詞組 + that 從句

It's a pity that he can't swim for his age . 真遺憾，就他的年齡來講，他竟不會游泳。

It's a wonder that you could finish such a hard task in such a short time . 真奇怪，你竟能在如此短的時間內(nèi)完成艱巨的任務(wù)。

可用于該句型的名詞詞組還有：an honour , a good thing , a fact , a surprise , good news等。

3) It + be /seem + 形容詞 + that 從句

It is likely that they will beat us tonight .今晚很可能他們會贏我們。

It doesn't seem that she will give us a hand .她幫我們的可能性似乎不太大。

可用于此句型的開容詞還有；wonderful , true , good , right , wrong , (un)important ,useless , surprising , clear , possible , unusual , lucky , certain 等。

4) It + seem / appear / happen + that 從句

It seems that he enjoys pop songs very much .看來他非常喜歡流行歌曲。

It appears that Tom might change his mind .看來湯姆會改變主意。

It happened that I went out that day .碰巧我那天外出了。

注意，句型4可轉(zhuǎn)換成含不定式的簡單句。如上述句子可轉(zhuǎn)換為：

He seems to enjoy pop music very much . / Tom appears to change his mind ./ I happened to go out that day.

6.  It / This / That + the first(second , third …) time + that-clause

這個句型表示截止到說話時為止的某人的一種經(jīng)歷，關(guān)鍵是注意time前有序數(shù)詞，主句是 is 時 ，從句要用現(xiàn)在完成時；如果主句用一般過去時was ，則從句須相應(yīng)地用過去完成時。例如：

This is the first time (that) these Europeans have visited the Great Wall .

It was the fifth time (that) I had paid a friendly visit to Africa .

二、It代替從句作形式主語的常見句型

5.   It + be + time +  that-clause

這個句型屬虛擬語氣結(jié)構(gòu)，不管主句中用的是 is 或 was ，that從句都須用動詞的過去式或should + 動詞原型(但不及用過去式普通)，在time之前有時可加上high或about 以加強(qiáng)語氣。例如：

 It is time(that)we handed in our exercises .(= It is time that we should hand in our exercises .)

It is high time  (that ) she wrote a letter to her boyfriend .

4.  It + be + 時間 + that-clause

這個句型是個強(qiáng)調(diào)句型。例如：

It was two years ago that he made an important invention .

(原句是：He made an important invention two years ago . )

It was at 5 o'clock that he practised playing the violin in the morning .

(原句是：He practised playing the violin at 5 o'clock in the morning . )

比較：It was 5 o'clock when he started in the morning .

(5 o'clock前沒有介詞，這是個定語從句)

3.  It + be + 時間 + when-clause

這個句型中, it 指時間，而且表示時間的詞語前沒有介詞(時間一般為具體時間)。主句中的謂語動詞和從句中的謂語動詞在時態(tài)上一般是一致的，主句是will be，when從句用一般現(xiàn)在時代替將來時。例如：

It was already 8 o'clock when we got home .

It was the next morning when we finished our work .

It will be midnight when they get there .