考研英語：區(qū)分定語和同位語從句

　　兩種從句的區(qū)別主要在以下三方面:
　　?從詞類上區(qū)別
　　同位語從句前面的名詞只能是idea, fact, news, hope, belief, suggestion, proposal, word, thought, doubt, truth, possibility, promise, order等有一定內(nèi)涵的名詞，而定語從句的先行詞可以是名詞、代詞，主句的一部分或是整個主句，如: The possibility that the majority of the labor force will work at home is often discussed.人們經(jīng)常討論大多數(shù)勞動力將會在家里工作的可能性。(同位語從句)
　　Our team has won the game, which made us very happy. 我們的隊贏了,這讓我們很高興。(定語從句)

　　?從性質(zhì)上區(qū)別
　　定語從句是從句對其先行詞的修飾或限制,屬于形容詞性從句的范疇;而同位語從句是從句對前面抽象名詞的進一步的說明和解釋,屬于名詞性從句的范疇，如: The news that our team has won the game was true. 我們隊贏了那場比賽的消息是真的。(同位語從句,補充說明news到底是一個什么消息。)
　　The news that he told me yesterday was true. 昨天他告訴我的那個消息是真的。(定語從句,news在從句中作told的賓語。)

　　?從引導詞及其在句子中的成分上區(qū)別
　　有些引導詞如how, whether, what可以引導同位語從句,但不能引導定語從句，如:
　　That question whether we need it has not been considered. 我們是否需要它這個問題還沒有考慮。(同位語從句)
　　引導詞that引導定語從句時,在從句中一般做主語或賓語(指物時還可以用which代替),并且作賓語時常常省略，that在同位語從句中僅起連接作用,不充當任何成分,并且不能省略,也不能用which來代替，如:
　　The order that we should send a few people to help the other groups was received yesterday. 我們應派幾個人去幫別的幾個小組的命令昨天收到了。(同位語從句,是對order的具體解釋,that雖不作成分,但不能省略。)
　　The order that we received yesterday was that we should send a few people to help the other groups. 我們昨天收到的命令是我們應該派幾個人去幫助別的幾個小組。(定語從句,是名詞order的修飾語,that在從句中作received的賓語,可以省略。)

　　【真題例句】The issue of whether life ever existed on the planet, and whether it persists to this day, has been highlighted by mounting evidence that the Red Planet once had abundant stable, liquid water and by the continuing controversy over suggestions that bacterial fossils rode to Earth on a meteorite from Mars.

　　【解析】句子可拆分為：The issue of //whether life ever existed on the planet, and whether it persists to this day, //has been highlighted //by mounting evidence //that the Red Planet once had abundant stable, liquid water and //by the continuing controversy over suggestions //that bacterial fossils rode to Earth on a meteorite from Mars.

　　主句為：The issue of whether life ever existed on the planet, and whether it persists to this day, has been highlighted by… and by…。主句主語的結(jié)構(gòu)為: The issue of whether…and whether…。of 短語修飾the issue, of 短語較長一般譯在后面；that the Red Planet…是evidence的同位語從句，（即evidence的具體內(nèi)容）。that bacterial fossils…是suggestions的同位語從句，說明suggestions的具體內(nèi)容。）第一個同位語從句可以直接翻譯在所修飾詞后面。第二個同位語可以放在所修飾的名詞前面，充當定語。

　　【參考譯文】越來越多的證據(jù)表明，這個紅色行星上曾經(jīng)有穩(wěn)定而豐富的液態(tài)水，而且人們對從火星落到地球上的細菌化石隕石的說法一直有爭論，使火星上是否存在過生命和是否至今仍有生命的問題成為了引人注目的重點。

　　（實習編輯：劉明忠）