而考生復習英語，語法也是必通關的基礎項目之一。根據歷年來看，新東方在線總結三大難點語法為大家詳解，一起來看下。

【as用法】

一、as引導定語從句

as引導定語從句時，既可以引導限定性定語從句，又可以引導非限定性定語從句。區分as引導定語從句和其它從句的關鍵特征是：as引導定語從句時在從句中做成分，通常做主語或賓語。

1、as引導限定性定語從句。

如從句所修飾的名詞前有such、the same、as出現，后面的定語從句將由as引導，形成such...as，the same...as，as…as這樣的固定結構，譯為“和……一樣”。

例1：I never heard such stories as he told.

我從未聽過他所講的那樣的故事。

例2：He’ll repeat such questions as are discussed in the book.

他將重復書中討論過的問題。

例3：They made the same mistake as others would have made on such an occasion.

他們犯了和其他人在這種場合下會犯的同樣錯誤。

2、as引導非限定性定語從句。

as引導非限定性定語從句，往往指代一整句話，通常表示“正如”的意思。as引導的非限制性定語從句位置相對比較靈活，可以位于先行詞之前、之后或中間。

例：As is known to everybody, the moon travels round the earth.

眾所周知，月亮繞著地球轉。

二、as引導時間狀語從句

as引導時間狀語從句多用于口語，強調“同一時間”或“一先一后”，有時還有“隨著”的含義。

例1：As I was going out, it began to rain.

當我出門時，開始下雨了。(as強調兩個動作緊接著發生，不強調下雨的特定時間。)

例2：As time goes on, he will understand what I said.

隨著時間的推移，他會理解我所講的話。

三、as引導原因狀語從句

as表示“因為”，與because相比，較口語化，所表達的原因語氣較弱，所表的原因比較明顯，或是已知的事實。

例1：As the weather is so bad, we have to delay our journey.

因為天氣太糟糕，我們不得不推遲旅行。

例2：Any new source of energy will be very welcome, as there is already a shortage of petroleum.

任何新型能源都將大受歡迎，因為石油已經出現短缺。

四、as引導方式狀語從句

as表示“按照”，“以……方式”，“像……一樣”，“正如”。

例：Do as the Romans do when in Rome. 入鄉隨俗

注：as在引導方式狀語從句時，還常出現在一個固定的類比結構中：(just) as …, so…。這一句型表示類比，基本含義是“正如……，所以……”。

例：Just as virtue is its own reward, so is vice its own punishment.

善有善報，惡有惡報。

五、as引導讓步狀語從句

as可以表示“盡管”，“雖然”，引導讓步狀語從句，但必須構成倒裝。讓步狀語從句倒裝規則有兩類：

1、 形容詞/副詞/分詞/名詞(無冠詞)/介詞短語等+as+主語+謂語動詞，主句。

例1：Much as I like you, I couldn’t live with you.

我盡管很喜歡你，卻不能和你在一起生活。

例2：Child as he is, he knows to help others.

盡管他是個孩子，他懂得幫助別人。

2、動詞原形+as+主語+助動詞(may/might, will/would, can/could, do/does/did)，主句。

例：Try as we may, we cannot sense directly the television signal sent out from the broadcast station.

盡管我們費了很大的勁，也無法直接覺察發射臺發出的電視信號。

六、as引導比較狀語從句

as引導比較狀語從句，其基本結構是as…as。前一個as是副詞，后一個as是比較狀語從句的連詞。否定結構為not so much … as …。

例1：Small as it is, the ant is as much a creature as are all other animals on the earth.

盡管螞蟻很小，但是它同地球上的任何其他動物一樣，也是一種動物。

例2：It was not so much the many blows he received as the lack of fighting spirit that led to his losing the game.

與其說是他受到了許多打擊，還不如說是缺乏斗志使他輸掉了比賽。

【that用法】

一、that 作限定詞或代詞

that可以作限定詞或代詞連接名詞或名詞短語，也可單獨使用，用以指代人或者物。此外，that不僅可以指代單獨的人或物，還可以指代一句話。

例：Furthermore, in the early days of long line fishing, a lot of fish were lost to sharks after they had been hooked. That is no longer a problem, because there are fewer sharks around now. [2006, text3]

分析：

A.分析句子結構。Furthermore, in the early days of long line fishing, a lot of fish were lost to sharks //after they had been hooked. That is no longer a problem, //because there are fewer sharks around now.

第一個句子的主句為a lot of fish were lost to sharks，介詞短語in the early days of long line fishing作狀語，after引導時間狀語從句。第二個句子主句是That is no longer a problem, that為代詞，because引導原因狀語從句。

B.分析that指代。that指代第一句話，“a lot of fish were lost to sharks after they had been hooked”，其中after引導時間狀語從句。

C.譯文：而且，在使用多鉤長線捕魚的初期，許多魚被鉤住后又被鯊魚奪走。這不再是一個問題，因為附近的鯊魚更少了。

二、that作副詞表示程度，相當于so

例：It isn’t all that cold. 天沒有那么冷。

三、that作連詞引導各類從句

(一)that引導名詞性從句

that后面連接一個完整的陳述句，可以位于主語、賓語、表語或同位語的位置，分別引導主語從句、賓語從句、表語從句和同位語從句。此時，that沒有實意，而且不在從句中做任何成分。that引導主語從句和同位語從句時不可以省略。

例1：That the plates are moving is now beyond dispute. (主語從句)

地球板塊是在漂移的，這一事實毋庸置疑。

例2：The truth is that everyone should take care of orphan, not just the authorities.(表語從句)

事實是，所有人都應該照顧孤兒，而不僅僅是完全由政府承擔。

例3：All people believed that it was right to rescue the temple. (賓語從句)(注：that可以省略)

所有人都認為拯救古廟是正確的。

例4：The students expressed their hope that they could be admitted by that university.(同位語從句)

學生們表達了他們向被這所大學錄取的愿望。

(二)that引導定語從句

that引導定語從句，在從句中充當主語、表語或者賓語，既可以指代人，也可以指代物。that在定語從句中作賓語時，引導詞that可以省略。

例1：The professor that you admire most will visit our university next month.

你敬仰的那個教授下月會到我們學校參觀。

例2：This is one of the subways that will be put into use in two years.

這是未來兩年內將開通的地鐵之一。

例3：I have nothing that is worth reading.

我沒有什么值得一讀的東西。

(注：當先行詞中有不定代詞、形容詞最高級、序數詞或者先行詞被the only，the very等限定詞修飾等情況下，定語從句引導詞也只能用that。)

(三)that與其他單詞結合引導狀語從句

that可以和其他單詞結構共同引導狀語從句，例如such...that，so...that等引導結果狀語從句，in order that，so that等引導目的狀語從句，in that，now that，on the grounds that等引導原因狀語從句，suppose/supposing/assume/assuming/provided/providing that，on condition that等引導條件狀語從句等。

例1：She has made such rapid progress that before long she could pass the exam.

她進步很快，不久就能通過考試的。

例2：You should make full use of this opportunity so that you can get rich experience.

你應該充分利用這次機會，以便獲得豐富的經驗。

例3：Supposing that you were in my position, what would you do?

如果你在我的位置，你會怎么做?

例4：On condition that you were lost in the desert, you should ask for help as soon as possible.

如果你在沙漠中迷路，你應該盡早尋求幫助。

(四)that引導強調句

“It is/was+被強調部分+that從句”是高頻使用的一種強調句型，其中被強調部分可以作從句的主語、賓語和狀語等。強調句中去掉“it is/was”和“that”后，句子成分和語義仍然完整。

例：It was after the war was over that Einstein was able to come back to his research work again.

戰爭結束后愛因斯坦才能重新進行他的研究工作。

【倒裝句】

一、全部倒裝

(一)there be句型

有時一些表示存在意義的不及物動詞也可用于該句型，如：stand， lie， exist， live， remain，appear， come， happen， occur， rise等。

例句：Generally, there was a belief that the new nations should be sovereign and independent states, large enough to be economically viable and integrated by a common set of laws. (選自2007年Use of English)

分析：該句是復合句，其中a belief與that the new nations should be sovereign and independent states互為同位語關系，形容詞短語large enough to be...作定語修飾states。

譯文：他們普遍認為新生的國家是擁有主權和完全獨立的國家，大到經濟上可運行良好，并由一套共同法律讓各個新的獨立國家聯合起來。

(二)表示方向、地點的狀語等詞置于句首

here， there， up， down， away， in， out， off等位于句首時，往往主謂倒裝。

例句： Here is an example, which I heard at a nurses convention, of a story which works well because the audience all shared the same view of doctors.(選自2002年Text 1)

分析：該句是復合句，which I heard at a nurses convention和which works well共同修飾story。

譯文：舉個例子，在一次護士大會上，我聽到了一個效果很理想的幽默故事，因為聽眾都對醫生持有相同的看法。

(三)作表語的形容詞或分詞置于句首

例句： Lying unconsciously under the tree was an old man aged 75.

分析：該句是簡單句，aged 75修飾an old man，作后置定語。

譯文：一位75歲高齡的老人躺在樹下，已經不省人事。

二、部分倒裝

(一)否定詞或具有(半)否定意義的詞或詞組置于句首作狀語

如：never， scarcely， hardly， rarely， seldom， little， no sooner...than，hardly...when，scarcely...when (before)， not only， in no case (in no way， at no time， on no account， by no means，under no circumstances，in no respects)(決不，在任何情況下都不)，no longer/no more (不再)。

例句： Television is one of the means by which these feelings are created and conveyed and perhaps never before has it served so much to connect different peoples and nations as in the recent events in Europe. (2005年第46題)

分析：該句是復合句，and前是一復合句，定語從句by which...修飾the means，后一分句中never置于句首引起倒裝。

譯文：電視是制造和表達這些情緒的方式之一，在加強不同民族和國家之間的聯系方面，電視也許還從來沒有像在歐洲事務中那樣起過如此大的作用。

(二)only+副詞/介詞短語/狀語從句(句首狀語由only修飾)

例句： Only recently did linguists begin the serious study of languages that were very different from their own. (選自2004年Part B)

分析：該句是復合句，that were very different from their own是修飾languages的定語從句。

譯文：直到最近，語言學家才開始認真研究與他們自己所掌握的完全不同的語言。

例句： Only gradually was the byproduct of the institution noted, and only more gradually still was this effect considered as a directive factor in the conduct of the institution.(2009年第47題)

分析：該句是由and連接的兩個并列簡單句，兩個分句都是以only開頭的倒裝句，在前一分句中，主干部分是the byproduct of the institution was noted， only gradually修飾noted;在后一分句中，主干是this effect was considered...，其中only more gradually修飾considered, as a directive factor作主語this effect的補足語，介詞短語in the conduct of the institution作directive factor的后置定語。

譯文：人們只是逐漸地認識到制度這一副產品，而在運行這種制度的過程中，認識到這種效果具有指導性作用的時間則更加緩慢。

(三)條件從句中省略if

在虛擬語氣中，條件從句if省略時，倒裝到主語前的是助動詞should，had和系動詞were。

例句： Were the Times Co. to purchase another major media company, there is no doubt that it could dramatically transform a family run enterprise that still gets 90% of its revenues from newspapers. (1999年第13題)

分析：該句是復合句，were the Times Co. to purchase是一省略if的倒裝句，that it could dramatically...enterprise是doubt的同位語，而that still gets 90% of its revenues from newspapers是修飾enterprise的定語從句。

譯文：如果時代公司要收購另一家主流媒體公司的話，那仍舊靠報紙獲得90%收入的家族式企業的模式肯定會遭到它大刀闊斧的改革。

例句： Had it not been for the timely investment from the general public, our company would not be so thriving as it is.(1998年第10題)

分析：該句是復合句，had it not been...是一個省略if的倒裝從句，整個句子表示混合式虛擬語氣，主句表示與現在相反假設，從句表示與過去相反假設。

譯文：要不是公眾及時投資，我們公司不會像現在這么繁榮。

(四)其他部分倒裝情況

表示前面陳述的情況適合于后者，前面是肯定句，后面用so引導;前面是否定句，后面用neither或nor引導，省略倒裝句中的助動詞在時態和語態形式上與前面句子保持一致。。

例句： Americans no longer expect public figures, whether in speech or in writing, to command the English with skill and gift. Nor do they aspire to such command themselves. (選自2005年Text 4)

分析：該句是由nor引導的并列句。whether in speech or in writing的完整形式是whether they are in speech or in writing，表示讓步;介詞短語with skill and gift在句中作狀語修飾動詞command。

譯文：美國人不再期望公眾人物在演講或寫作時可以嫻熟地運用技巧和文采來掌握英語，而人們本身也不這樣要求自己。

(五)so...that結構

so...that結構中，“so+狀語”位于句首表強調時，使用倒裝。

例句： So involved with their computers do the children become that leaders at summer computer camps often have to force them to break for sports and games.(2001年第6題)

分析：該句是復合句，that leaders at summer computer camps...是一結果狀語從句，so involved with...置于句首引起倒裝。

譯文：孩子們對電腦如此著迷，以至于電腦夏令營的組織者們不得不強迫他們停下來做一些體育運動和游戲。

(六)not until置于句首

not until置于句首時，連詞until引導的從句主謂不倒裝，但主句的主謂結構必須倒裝。

例句： Not until you return those books to the library immediately will you have to pay a fine.

分析：該句是復合句。由于not until置于句首，主句will you have to pay a fine是一倒裝句。

譯文：只有及時還書給圖書館，你才不會受罰。

(七)as， though， no matter how， however引導的讓步狀語從句

as， though引導的倒裝句型為：名詞(前不加a或an)/形容詞/副詞+as+主語+謂語，該結構可用though引導的讓步狀語從句來替換，譯為“雖然…但是”或“盡管…但是”。

例句：Much as I have traveled, I have never seen anyone to equal her in thoroughness, whatever the job.

分析：該句是復合句，其中從句much as I have traveled是一倒裝句，短語“equal sb. in sth.”意為“在某方面與他人旗鼓相當”

譯文：雖然我常旅行，但我從未見過任何人于任何工作能像她那樣一絲不茍。

例句：Odd though it sounds, cosmic inflation is a scientifically plausible consequence of some respected ideas in elementary article physics, many astrophysicists have been convinced for the better part of a decade that it is true. (1998年第75題)

分析：該句是復合句，odd though it sounds是一倒裝句，其中it指代cosmic inflation，介詞短語in elementary article physics修飾ideas，that it is true在句中作convinced的賓語，另一介詞短語for the better part of a decade作狀語表示時間。

譯文：宇宙膨脹說雖然聽似奇特，但它還是基本粒子物理學中一些公認的理論在科學上看來可信的推論。許多天體物理學家十年來一直認為這一論說是正確的。

(八)be+主語+其他(若其他是單數名詞作賓語，則名詞前不接不定冠詞a/an)

這是一開放式條件狀語從句，屬于特殊倒裝結構，表示泛指。該結構可用whether...or結構來替換，同時單數名詞前的不定冠詞保持不變，可譯為“不管/不論……”。

例句：Church as we use the word refers to all religious institutions, be they Christian, Islamic, Buddhist, Jewish, and so on.(2001年第10題)

分析：該句是復合句，be they...是一倒裝句，相當于whether they are...。

譯文：我們所使用的教堂一詞，指的是所有的宗教機構，不管它們是基督教、伊斯蘭教、佛教或猶太教等。