1、as與which引導定語從句的用法辨析定語從句是高一英語的主要語法項目之一，也是高考英語的常考知識點，尤其是as和which引導的定語從句，更是歷年高考試題中的考點和熱點。as和which都能引導定語從句，那么它們的共同點和區別是什么呢? 一、as和which都能引導的定語從句 當非限定性定語從句置于句末時，as和which都可用來引導這個定語從句。例如： Dorothy was always speaking highly of her role in the play, _ , of course, made the others unhappy. (NMET2000) A. who B.

2、 which C. this D. what 【簡析】答案是B。which引導非限定性定語從句，指代前面主句的內容，定語從句部分意為：這當然使別人不高興。這里不能換用as作引導詞，因為我們不能說“正如使別人不高興”。 The number of senior high school students is increasing, _ is mentioned above. A. that B. it C. such D. as 【簡析】答案是D。as引導非限定性定語從句，意思是“正如”。此時也可以換用which引導，但意思有別，意為：這一點上面提到了。 二、只能用which引導的定語從句 1.

3、 在限定性定語從句中。例如： The project _ a British businessman has invested in is under construction at present. A. which B. as C. what D. why 【簡析】答案是A。單個詞引導限定性定語從句時，一般不用as。當然，本題中的定語從句也可以使用that引導；由于關系詞在從句中作賓語，which和that都可以省略。 2. “介詞+關系代詞”引導定語從句時，只能用which。例如： Recently I bought an ancient Chinese vase, _ was very

4、 reasonable.(上海2000高考) A. which price B. the price of which C. its price D. the price of whose 【簡析】答案是B。此時的which不能用as來代替。另外還應注意：引導定語從句時，which不能單獨作定語，此時不管先行詞是人還是物，都只能用whose引導，但指物時，可以與of which替換(如本題)。 3. 當后置的非限定性定語從句是否定結構時，只能用which引導。例如： The result of the experiment was very good, _ we hadn't expe

5、cted.(2000京皖春招) A. when B. that C. which D. what 【簡析】答案是C。由于非限定性定語從句是否定結構，只能用which引導，不能用as來替代which。 三、只能用as引導的非限定性定語從句 1. 置于句首時，非限定性定語從句只能用as引導。例如： _ is known to everybody, the moon travels round the earth once every month. (NMET2001) A. It B. As C. That D. What 【簡析】答案是B。As在定語從句中作主語，這里不能換成Which。 2.

6、在the same.as 結構中，意思是“像那樣的”。例如： Chongqing is not the same city _ we have seen in other places. A. that B. which C. 不填 D. as 【簡析】答案是D。as在定語從句中作have seen的賓語。the same . that的意思是“正是；就是”。注意：as不能省略。 3. 在as.as結構中，意思是“像那樣的”。例如： No period in history has had as many important changes _ have taken place in the

7、past century. A. which B. as C. that D. what 【簡析】答案是B。as引導定語從句并在從句中作主語。 小試牛刀： 1. _ has been announced, we shall have our final exam next month. A. That B. As C. It D. What 2. The weather turned out to be very good, _ was more than we could expect. A. what B. which C. that D. if 3. In the office I ne

8、ver seem to have time until after 5:30 pm, _ many people have gone home. A. whose time B. that C. on which D. by which time 4. Mathilde had to work hard day and night and bought such a diamond necklace _ she had lost to pay back to Jeanne. A. as B. that C. which D. 不填 5. Robert, is this yours? Yes,

9、it's just the same Walkman _ I lost on the playground yesterday. A. which B. what C. as D. that Key: 15 BBDAD as作從屬連詞用時，可以引導五種狀語從句。現歸納如下：1. as表示“當的時候”，引導時間狀語從句，多強調主句和從句中的動作或狀態同時發生，從句可放在主句前，也可放在主句后。例如： As I waited at the stop， I heard a big noise. 當我在車站等車的時候，我聽到一個很大的聲響。 She rose up as he entered.

10、 當他進來時，她站了起來。 2. as表示“因為”、“由于”，引導原因狀語從句，其語氣不如because強，通常為附加說明的理由，且是已知曉的原因，主句與從句沒有邏輯上的因果關系。例如： As she was not well, I went there alone. 因為她身體不好，所以我獨自到那里去了。 As he is a tailor, he knows what to do with this material. 由于他是個裁縫，他知道怎樣利用這塊布料。 3. as表示“雖然但是”，引導讓步狀語從句，從句通常用倒裝語序，把從句的表語、狀語或動詞原形放在as前面，可以用though替代

11、。例如： Child as he is, he knows a lot. 雖然他是個孩子，但他知道的東西很多。 Hard as it was raining， they went on working in the field.      雖然天下大雨，但他們繼續在田地里干活。 4. as表示“按照”、“依照”、“像”，引導方式狀語從句，從句置于主句之后。例如： You should do as the teacher tells you.你應當依照老師所說的去做。 The absence of air also explains why the stars do not seem to twinkle in space as they do from the earth.       空氣的不存在，也說明了為什么在空中星星看來并不閃爍，而不像從地球上看的那樣。 5. as表示“像一樣”，引導比較狀語從句，對主句和從句的動作或狀態加以比較，說明它們之間有相似