子句

我們討論子句時會用到的字

基本上，我們將子句分為獨立子句 (independent clauses)和從屬子句 (dependent clauses)；這意謂有些子句可以單獨存在，有些則不行。獨立子句又稱為主要主句 (main clauses 或 principal clauses)，而從屬子句又稱為附屬子句 (subordinate clauses)--意謂附屬子句必須依附主要主句才能存在。附屬子句是由附屬連接詞 (subordinating conjunction，又稱從屬字 dependent word：如 because, and, but, yet, so 等 ) 來產生。

請注意一個獨立子句在同一組字以一個從屬字做開頭時如何變成附屬子句，如 "She is older than her brother" 變成 "Because she is older than her brother, she tells him what to do."

子句也被分為限定子句 (restrictive clauses) 與非限定子句 (nonrestrictive clauses)。有兩個字有時也被用來分別表達跟 restrictive 和 nonrestrictive 相同的意思，那就是 「必要」(essential) 和「非必要」( nonessential)。一個非限定子句對句子的意思並非必要，它可從句子中移除而不會改變句子的基本意思。非限定子句通常用一個逗點與句子的其他部分分開，或者前後各用一個逗點分開 (如果它是放在句子中間的話)。

Professor Villa, who used to be a secretary for the President, can type 132 words a minute.

請再參考 "Which Vs. That" 以進一步瞭解限定與非限定子句之間的不同，及這些子句如何加標點符號。

關係子句 (relative clauses) 是由一個關係代名詞 (relative pronoun：that, which, whichever, who, whoever, whom, whomever, whose, of which等) 所引導的附屬子句。關係子句可以是限定或非限定子句。讀者可以參考「逗點的使用規則」，裨在決定關係子句是限定子句或非限定子句，以及是否使用逗點來將它們與句子的其他部分分開時，可以獲得更多的協助。在關係子句中，關係代名詞是動詞的主詞 (記住：所有子句都有主詞與動詞的關係)且與該子句前面的人事物有關。

Tom said that the plantar wart, which had been bothering him for years, had to be removed.

(在這個句子中，以黃色表示的子句為一限定子句，即必要子句 [名詞子句]，不可以用逗點分開；而加底線的關係子句 [修飾 "wart"]為非限定子句，即非必要子句 [可以自句子中移除而不會改變句子的意思]，則用逗點分開。)

精減子句 (Elliptical clauses)：見下面的說明。

獨立子句 (Independent Clauses)

獨立子句可做為單獨的句子存在，只是當它們與其他子句分離而單獨存在時，它們通常被稱為句子，而不叫子句。我們必須學會辨認子句並知道一個子句何時可以做為獨立子句，這有助於我們寫出正確的句子。例如，在下面的句子中，

Bob didn't mean to do it, but he did it anyway.

我們有兩個獨立子句-- "Bob didn't mean to do it" 和 "he did it anyway" --它們被一個逗點和一個對等連接詞 ("but") 連接起來。

當然啦！我們也必須學會將兩個或兩個以上的獨立子句結合為一個較長句子的技巧。例如，如果在上面的句子中，"but" 被拿掉，那麼這個句子就被稱為逗點謬誤 (comma splice)：兩個獨立子句之間僅用一個逗點來連接。再者，一長串結構與長度相似的子句會讓人覺得單調乏味，導致所謂 "Dick and Jane" (小學一年級學生的造詞造句；又稱 primer language__詳細解釋請參見英文資料庫之教育學術大醬缸)。因此，我們要避免小學生式的造詞造句。此時若能瞭解兩個獨立子句之間的標點符號，對你應該也有幫助。

子句係利用三種不同的方式來結合：對等、附屬及使用分號 (；)。對等 (coordination) 是指以一個對等連接詞 (and, but, or, nor, for, yet, so)來結合獨立子句。利用這種方式連接的子句在長度和意思 (import) 上通常具有良好的對等。

Ramonita thought about joining the church choir, but she never talked to her friends about it.

附屬 (subordination) 是指利用一個附屬連接詞 (有時稱為附屬字) 或一個關係代名詞將其中一個子句變成附屬子句。當某一子句係以附屬或從屬字做開頭時,他就不再是獨立子句；它被稱為附屬或從屬子句，因為它的意思係依附獨立子句而定。我們還可利用其他方法來結合子句，如將獨立子句變成各種修飾用的片語。

Although Ramonita often thought about joining the choir, she never talked about to her friends about it.
Ramonita never talked to her friends about joining the choir, because she was afraid they would make fun of her.
Yasmin is Ramonita's sister. Yasmin told Ramonita to join the choir no matter what her friends said.
利用關係子句來結合：
Yasmin, [who is] Ramonita's sister, told Ramonita to join the choir...

分號 (semicolon) 可以在連接副詞 (conjunctive adverb，亦稱語氣轉折字 transitional expression：however, moreover, nevertheless 等) 的協助下 (但也可以不必藉助於連接副詞) 連接兩個獨立子句。但分號應盡量少用，而且只有當兩個獨立子句在長度和意思上關係非常密切且具有良好的對等關係時才使用.

Ramonita has such a beautiful voice; many couples have asked her to sing at their wedding.
Ramonita's voice has a clear, angelic quality; furthermore, she clearly enjoys using it.

從屬子句 (Dependent Clauses)

從屬子句不能單獨存在。它們必須與獨立子句結合，成為一個可以單獨存在的句子的一部份。與獨立子句不同的是，附屬子句係被用來在句子中擔任不同的功能。它們可以當名詞用或當修飾語用。根據它們在句子中的功能，我們可以分類出三種基本的從屬子句。請記住：一個從屬子句一定包含一個主詞和一個動詞，但它不能單獨存在。

副詞子句 (adverb clauses) 提供有關主要子句「到底怎麼回事」的資訊：where, when, why。 "When the movie is over, we'll go downtown." 或 "John wanted to write a book because he had so much to say about the subject."
形容詞子句 (adjective clauses) 的功用有如多字的形容詞。 "My brother,
who is an engineer, figured it out for me." 或 "The bridge that collapsed in the winter storm will cost millions to replace."
名詞子句 (noun clauses) 具備名詞的所有功能。 "What he knows [主詞] is no concern of mine." or "Do you know what he knows [受詞]?" 或 "What can you tell me about what he has done this year [介系詞 "about" 的受詞]?"

1.名詞子句當主詞	What they did with the treasure remains a mystery. Whatever you want for dessert is fine with me. That you should feel this way about her came as a great surprise to us.
2.名詞子句當受詞	Juan finally revealed what he had done with the money. Her husband spent whatever she had saved over the years. I don't know what I should do next.
3.名詞子句當介系詞的受詞	In fact, he wrote a book about what he had done over the years. We are interested in what he does for a living.
4.名詞子句當述語主格 (predicate nominative) -- 即主詞補語	The trouble was that they had never been there before. The biggest disappointment of last season was that the women's team didn't make it to the final four.
5.形容詞子句	My brother, who now teaches math in a small college, never liked math in high school. The dealership that sold more cars ended up actually losing money. The Federated Bank, which was founded nearly two centuries ago, folded during the state's economic crisis.
6.副詞子句	The team had fallen behind by ten points before they were able to figure out the opponent's defense. Since he started working nights, he doesn't see much of his kids. While Josie sat inside watching television, Gladys shoveled the driveway.

精減子句 (Elliptical Clauses)

精減子句是文法不完整的子句，因為它們省略了通常用來引導這種子句的關係代名詞 (從屬字) 或一項比較中第二部分的述語 (predicate)。精減子句中省略的部分可以從上下文中猜測出來，而大多數讀者也不知道什麼東西不見了。事實上，精減子句被視為一種有用且正確的子句，即使在正式的文章中亦然，因為它們通常是優雅和有力的表達方式。在下面的句子中，被省略的字用括號括起來。

Coach Rodman knew [that] this team would be the best [that] she had coached in recent years.
Though [they were] sometimes nervous on the court, her recruits proved to be hard workers.
Sometimes the veterans knew the recruits could play better than they [could play].

Which Vs. That

Which 這個字可被用來引導限定子句與非限定子句，不過許多寫作者僅用它來引導非限定子句；That 這個字只能被用來引導限定子句。看看下面這兩個句子之間到底有什麼不同：

"The garage that my uncle built is falling down."
"The garage, which my uncle built, is falling down."

無論在什麼地方，當我說出第一個句子時，聽的人一定都確切知道我講的是那個車庫 -- 我伯父所蓋的車庫。然而，在第二個句子中，我必須說出車庫的位置，如在我家的後院，同時指著該倒塌的車庫。換言之，"that 子句" 已提供你需要的資訊，否則你將不知道我講的是那個車庫 (所以不需要逗點，也不可以有逗點)；"which 子句" 則提供非必要、附加的資訊 (所以需要逗點)。順便一提的是，若干寫作者堅持 that 這個字不能用來指人，但在這些人未被指名道姓的情況中，這種用法是可以的。

The students that study most usually do the best.

(但我們這樣寫 "The Darling children, who have enrolled in the Lab School, are doing well." 也沒有錯)