形式主語是一個代詞

1、個IT,就是形式主語”可是樓主所舉的句子能換位嗎？從表面上看，第一句話說成“Who didthe experiment in the lab yesterday evening was my fa ther.好像沒有什么語法錯誤， 但是這里卻 存在致命的邏輯錯誤。如果句子主語是Who引導(dǎo)的主語從句，那么動作的發(fā)出者就成了我爸爸（who是連接代詞）昨晚在實驗室里做實驗”注意：我爸爸昨晚在實驗室做實驗”這是一件事，可不是一個人，所以后面怎么能接“was my father呢”如果這樣寫，那么句子直譯過來就是我爸爸昨晚在實驗室里做實驗是我爸爸。"這語言是不是很后現(xiàn)代？那么這句話能不能改對呢

2、？答案是能，而且可以改得非常漂亮，非常地道，只要加一個代詞就可以了，我把它改成 “ He who did the experiment in the lab yesterday evening was my father.（順y便說一句，雖然很多人，也包括絕大多數(shù)老師，都喜歡與The man who，但是有央文閱讀習(xí)慣的人一般都認(rèn)為He/Shewho 的表達(dá)更加地道，當(dāng)然前者也沒有任何錯誤。）發(fā)現(xiàn)了么？這么一改，“ Who引導(dǎo)的從句就成了 定語從句，而句子的主干則成了 “ He was mfather.，邏輯錯誤消失了。問題2:這里的問題和上面完全一致，所以樓主能把這兩個問題捆綁起來提冋也很咼

3、明。what做連接詞的時候永遠(yuǎn)等于thething（s） that，那么如果用1what的話，顯然就是把句子當(dāng)成形式主語IT引導(dǎo)的句子，而不是 強調(diào)句了，于是它可以把主語還原，變成“Thething that attracted the audienee's interest was how the young man haclearned five f oreign Ianguages.，而這句話顯然是正確的。于是，冋題變成了為什么一疋要把這句話看成強調(diào)句，而不能把它當(dāng)成IT作形式主語呢？ 答案是，因為如果不掉過來，這句話是錯的。我們退回一步，用取簡單的方式還原，這句話成了It wa

4、s how the you ng manhad lear ned five foreig n Ian guages the thi ng that attracted the audie nee's in terest.樓主，這話通順嗎？是不是很別扭？能告訴我別扭在哪里嗎？這話別扭在，IT作形式主語只能代名詞性結(jié)構(gòu)（從名詞性短語、動名詞、名詞性從句），它代不了名詞+定語從句的結(jié)構(gòu)。怎么改？在問題1中，我們添了個主語， 把主語從句變成了定語從句，這里我們反其道而行之， 給它去掉主語“the thing，把定語從句還原回主語從句，于是，強調(diào)句的結(jié)構(gòu)就出現(xiàn)了。所以歸根結(jié)底，強調(diào)句和IT作形式

5、的主語的區(qū)別是什么？是that/who所引導(dǎo)的句子是能夠獨立作主，還必須修飾別人的區(qū)別；如果能夠獨立從當(dāng)主語而不會出現(xiàn)邏輯錯誤，那它就是IT作形式主語；反之，必須通過添主語的方式把它改造成定語從句，讓它修飾新添加的主語句子邏輯上才能通順，那它就是強調(diào)句。第一部分常規(guī)主語從句，即句子在復(fù)合句中充當(dāng)一個 主語主語從句的時態(tài)：不受主句的時態(tài)影響和限制。（1）That he finished writing the eomposition in such a short time surprised us all.（2）Whether we will go for an outing tomorrow

6、 remainsI T 9 !H> WMRM 巴 W 4-ih feafN- ife liW IPw 1 |1管 lA Ifajr*k3nDrrs nanaM.ll> w h w14* wwh *> I !. fc WW.wM hbm uhbwk* 利!>1耳IW M4| ElI” WWI Hwunknown.（3）Who will be our mon itor has n't bee n decided yet.（4）Whom we must study for is a question of great importanee.（5）What caused

7、 the aeeide nt rema ins unknown.（6）Whatever you did is right.（7）Who the watch belongs to was lost is unknown.（8）What we n eed is time.（9 ） What we n eed are good doctors.小結(jié)（1）引導(dǎo)主語從句連詞有that,whether,who,what,whatever 等（2）連詞位于句首不能省略（3 ）主語從句大多數(shù)情況下視為第三人稱單數(shù)，但也有例外，如例（9 ）為了防止句子頭重腳輕，通常把形式主語it放在句首位置，真正主語擱置于句末

8、（1）It is certain that he will win the match.（2）It is true that he has made a very important discovery in chemistry.（3 ） It is very likely that they will hold a meeti ng.（4 ） It is stra nge that he should do that.（5 ） It is important that we all should attend the meeting.（6 ） It is strange that the m

9、an should have stuck to his silly ideas.（7 ） It is a pity that we won't be able to go to the south to spe nd our summer vacatio n.（8 ） It is still a mystery what caused the accide nt.（9 ） It is said that he has gone to sha nghai.（=He is said to have gone to sha nghai）（10）It is known to all that

10、the gun powder was first inven ted by the Chin ese.（11）It is suggested that the work should be done with great care.（12）It happe ned that the two cheats were there. （=The two cheats happe ned to be there）小結(jié):（1） 為避免頭重腳輕，常以形式主語it引導(dǎo)從句。lt+形式主語謂語+從句。（2） 由于主語從句一般被認(rèn)為是單數(shù)形式，形式主語的謂語動詞、be動詞+表語 均 為單數(shù)第三人稱形式或過去式.

11、主語從句的用法紹。一.主語從句主語從句 定義：在句子中擔(dān)當(dāng)主語的是一個從句，這個從句就叫做主語從句。主語從句是在復(fù)合句中充當(dāng)主語的從句，通常放在主句謂語動詞之前或由形式主語it代替，而本身放在句子末尾。1. It作形式主語和it引導(dǎo)強調(diào)句的比較 主語從句常用it作形式主語，一般常用句型為：It is+名詞/形容詞/過去分詞+主語 從句例如：It is still a question whether she will come or not.It is stra nge that you should like him.It is still unknown which team will w

12、in the match.另外，還有一些比較多見的結(jié)構(gòu)：It turned out that ；It has bee n proved that ；It happe ned/occurred that ；It is well- known that 等等 而強調(diào)句則不同，它的結(jié)構(gòu)是： It+be+被強調(diào)部分+that+從句強調(diào)主語：It is the times that produce their heroes.時勢造英雄強調(diào)賓語：It is En glish that Prof.L in teaches us.強調(diào)狀語：It was in sha nghai that I saw the

13、film.判斷是否是強調(diào)句有一個方法，就是將that以后的句子的其余部分”拿出來單獨看，看有沒有缺成分，缺的是什么成分，再把謂語動詞后面that前面的那部分，帶到你認(rèn)為缺成分的地方，如果放進(jìn)去是一句 完整的句子了，那就說明是強調(diào)句。2. 用it作形式主語的結(jié)構(gòu)It is + 名詞+that從句It is a fact that 事實是It is an honor that 非常榮幸It is com mon kno wledge that-是常識(2) it is + 形容詞+that從句It is natural that很自然It is stran ge that 奇怪的是(3) it +

14、不及物動詞+that從句It seems that 似乎It happe ned that 碰巧it is+ 過去分詞+that從句It is reported that 據(jù)報道It has been proved that已證實 3主語從句不可位于句首的五種情況(1) if引導(dǎo)的主語從句不可居于復(fù)合句句首。(2) It is said , (reported)結(jié)構(gòu)中的主語從句不可提前。例如：It is said that Preside nt Jingo will visit our school n ext week.(3) It happe ns ,It occurs結(jié)構(gòu)中的主語從句不可

15、提前。例如：It occurred to him that he failed in the exam in ati on.It doesn' t matter how/whether結(jié)構(gòu)中的主語從句不可提前。例如：It doesn ' t matter whether he is wrong or not.(5)含主語從句的復(fù)合句是 疑問句時，主語從句不可提前。例如:Is it likely that it will rain in the eve ning?4. What與that在引導(dǎo)主語從句時的區(qū)別What引導(dǎo)主語從句時在從句中充當(dāng)句子成分，如主語賓語表語，而that則

16、不然。例如：What you said yesterday is right.二：賓語從句用以區(qū)分主語從句的幾個特征：1、引導(dǎo)詞:whatwhichwhosewhenwhetherifwhere2語序：賓語從句必須是用陳述語句。如: I think that you must work harder.賓語從句的引導(dǎo)詞、 連接詞的區(qū)別、否定轉(zhuǎn)移 等現(xiàn)象。(1) 表達(dá)時間的幾個句型：一般用 when或者是what time :What time will the train leave?由于時刻都是固定的，也可以用一般現(xiàn)在時代替一般將來時：What time does the train leave?(2) 時間的表達(dá)方式：8： 19(nineteen past eight),7:57(three to eight) ，在時間的中間也可以加上分的單詞 (mi nu tes)(3) had better +動詞原型。意思是提要求，建議。但是上下級不能用這種方式，因為語 氣太重：You had better give up smok ing .(4) sb leave sth + 地點