英語四六級可能出現的語法知識
英語四六級考試中閱讀翻譯、寫作、選詞填空，沒有不用語法的。大家如果在備戰這項考試的時候，一定要注意相關語法的運用。今天來看看英語四六級考試常見的語法考點，說不定對你的備考就有幫助呢!感興趣的朋友快跟上來吧!
一、定語從句
引導定語從句的有關係代詞 as，who，whom，whom，which，that 和關係副詞when，where， why 等。
引導定語從句
(1)as 引導定語從句，相當於 which。如 I am from shanghai，as/which you know.
但 as 引導的定語從句可以放在句首，而 which 不能;
例：As you know，1am from shanghai。
(2)as 可作爲關係代詞來引導定語從句，既可以單獨引導從句，又可以與主句中的 the same 或 such 相呼應，從句中的謂語動詞常省略。
2.關係代詞 that 與 which 用法區別：
(1)which 可以引導一個非限制性定語從句，that 則不能;
(2)which 之前可以有介詞，that 之前則不能;
(3)只能用 that，而不能用 which 的主要情形:
——當先行詞是 all，anything，few，litule，much，none、nothing，something 等不定代詞時：
——當先行詞被序數詞或形容詞最高級修飾時;
——當先行詞被 the very，the only 等詞修飾時。
例：Medical researchers are painfully aware that there are many problems to which they have not found solutions so far.
二.狀語從句
1.讓步狀語從句
(1)由 no matter + wh-疑問詞【no matter what】和 wh-疑問詞+ever【whatever】。但 wh-疑問詞+ever 【whatever】引導的名詞從句則不能用 no matter替換。
Take the coat , no matter what coat it is / whatever coat it is.
(2) No matter whether...or...結構中可將 no matter 省略，形成 whether...or..或 whether...or not 引導選擇條件句。
例; The substance does not dissolve in water whether {it is}heated or not.
2.條件狀語從句
翻譯條件狀語從句時，要注意時態的選擇。
例;Please come here at ten tomorrow morning if it is convenient for you。條件狀語
從句，用if引導;主句是祈使句，相當於將來時態，故從句應用一般現在時。
3.時間狀語從句
例;We do not know it until a doctor discovered it by chance 。
4.原因狀語從句
常見引導原因狀語從句的引導詞有;because，as，now that/since， in that等。
三.名詞性從句
1.主語從句
漢語中的“的”字結構可譯成英語的主語從句，用 what 引導，相當於 the thing that.
例: What many people have not realized is that read books is a insteresting thing.
2.表語從句
In my seventies, one change I notice is that I am more easily to get tired than before.
四.比較結構
...as【與...一樣】，more..than 【比...更】，a bit/a little/a lot/even/far/gretly/many/much/sightly/still-+形容詞/副詞比較級這些結構。
注意：more than 表示“不只是，只不過”;no more... han...not..any more than..,表示‘與...一樣不...”。
例：I would prefer shopping online to shopping in a department store because it is
more convenient and time-saving.
例：Since my childhood I have found that nothing is more attractive to me than
reading.
2. The more...the more...“越...越...”
例：The more you explain ，the more confused me。
3.倍數表達法
——A is 倍數+the size/length/width of B 【A是B 的幾倍大/長/寬】
——A is 倍數+形容詞或副詞原級+as B 【A 是 B 的幾倍】
——A is 倍數 more than B 【A 是 B的幾倍】
例：On average,it is said, visitors spend only half as much money in a day in Leeds
as in London.
4.表示與...相比較的短語 compare with 和 in comparison with
例：Your losses in trade this year are nothing compared with/in comparison with mine。
五.情態動詞
1.情態動詞中的 must，can，could，may，might都表示推測。其中 must 可能性最大，can 和 could 其次，may 和 might 最小。
2.情態動詞完成時所表達的意義：
——could have done 本可能做
——may/might have done 也許做了
———should have done 本應做
——must have done 肯定做過
六.倒裝結構
1.有否定含義的副詞或短語位於句首作狀語，這類詞有：neither，never, no, rarely, hardly...when, little，few， in no case ，no sooner...than等。
例:Not until he fanish his work did he realize he was seriously ill.
2.含有 only的狀語或賓語位於句首時，其句子的主謂要部分倒裝。
例：Not only did he charge me too much，but he completed his mission。
3.虛擬語氣的讓步狀語從句中，在省略了 If的情況下主謂部分倒裝。
Had I taken your advice 【ifI had taken your advice 】, all this misery might have
been avoided.
七.虛擬語氣
①would rather+that從句+一般過去時;
②It vital / necessary / important /urgent/ imperative /desirable /advisable /natural/ essential+that+(should)動詞原形;
③proposal/suggestion+that+動詞原形;
④it is time/about time/high time+that+一般過去時;
⑤lest+that+should+動詞原形;
⑥if only+that+would+動詞原形。
英語四六級考試的相關考點大家要弄懂，平時的訓練也要努力，這樣在考試中才有可能取得好成績。
