從屬連接詞 (Subordinating Conjunctions)

從屬連接詞，又稱附屬連接詞，它是複句的基本組成部分。從屬連接詞主要是在句子中兩種概念之間提供了必要的轉變，此轉變牽涉到時間、地點、條件或因果關係。以「從屬連接詞」所引導的從屬子句與主要子句結合形成為一個複句。從屬子句在某種程度上是用來修飾主要子句，它與主要子句同樣具有主詞與述部，但主要子句可單獨存在，從屬子句卻無法單獨存在，它必須依附在主要子句，所以才有「附屬」這個稱謂。

常見的從屬連接詞有：

I can't reach Andy because he has gone fishing.

我不能連絡上 Andy, 因為他釣魚去了。

從屬連接詞 because 引導的從屬子句 "because he has gone fishing" 修飾主要子句 "I can't reach Andy" ，說明原因。

She looks younger than she is.

她看起來比她實際年齡要年輕。

My mother-in-law treats me as if I am her enemy. I am blamed whenever something goes wrong.

我的岳母對待我就像是她的敵人。每當不順心的事發生時，我就被指責。

When the woman read the letter, her eyes welled up with tears.

當這婦人讀了這封信時，她熱淚盈眶。

"well" 當動詞解釋時有「（液體慢慢地）湧出」的意思。
"welled up with tears" - 熱淚盈眶。

As long as Taiwan is strong enough, Taiwan will not become a battlefield.

只要台灣足夠強大，台灣就不會成為戰場。

從屬連接詞 as long as 引導的從屬子句 "As long as Taiwan is strong enough" 修飾主要子句 "Taiwan will not become a battlefield" ，說明條件。

從屬連接詞的字彙要比對等連接詞(and, but, or, nor, for, so, yet)來得多，下面是一些常用的從屬連接詞依使用方法分類。

從屬連接詞 Although, Even though, Though

從屬連接詞 although, even though, though 用於連結「對比」（相反或差異）的兩件事，它們與對等連接詞 'but' 的用法類似。

He is rich but he is not happy.

他很富有，但他並不快樂。

對等連接詞 but （但是），連結對比的兩件事：“他很富有” 與 “他並不快樂”。

Although he is rich, he is not happy.
He is not happy although he is rich.

儘管他很有錢，但他並不快樂。

以從屬連接詞 although （儘管，despite the fact that）起頭的從屬子句，與主要子句所呈現的信息形成一種令人驚訝或意外的對比。

Even though he is rich, he is not happy.
He is not happy even though he is rich.

即使他有錢，他也不快樂。

even though 除了語氣要比 although 稍強些，兩者意義大致相同，even though 與 although 是可以互換的。
注意：句子若含有 although 或 even though，不能再有 but。

Though it was raining, we went hiking.

儘管下著雨，我們還是去健行。

Though she tried very hard, she failed the test.

儘管她非常努力，她仍未通過考試。

Though - "雖然，儘管" 。
though, although, 與 even though 都可以作為從屬子句的起頭，說明對比的兩件事。

我們常看到兩個對比的句子緊跟在一起，在第二個句子之後加上逗點『, 』，『though』，這個 though 在文法上是作副詞用，但也有連結前面一句的意涵， 表示 "可是，不過，然而"。

He is rich. He is not happy, though.

他很富有。然而他並不快樂。

That watch was expensive. I bought it, though.

那手錶很貴。 不過我買了。

我習慣買便宜的東西，我不喜歡昂貴的，但那只錶我卻花大錢買了。

Our team lost. It was a good game though.

我們的團隊輸了。 然而這是一場精彩的比賽。

though 前面的逗點『, 』，並非絕對必要，省略掉也無所謂。

表時間的從屬子句是由 after, before, while, when, as, until, by the time, as soon as 之類的連接詞起頭所形成。

When the phone rang, I was taking a shower.

當電話響時，我正在洗澡。

I was taking a shower when the phone rang.

表時間的從屬子句可以放在主要子句之後，這時候就不需要用逗點來隔開兩個子句。

上面例句的主要子句的動詞是過去進行式(was taking)，從屬子句的動詞用的是過去式(rang)。請特別注意：當主要子句的動詞是未來式時，從屬子句的動詞通常是用現在簡單式，不可以用 will 或 be going to。

Until the boss shows up, we are not going to leave.

直到老闆出現，我們是不會離開的。

主要子句的動詞 are not going to leave 是未來式時，從屬子句的動詞用現在簡單式 shows up，這裡不能用 will show up。

• 當江蕙小姐一到達時，我們的晚會就開始。
• As soon as Ms. Jody Chiang will arrive, we'll start the party.
• As soon as Ms. Jody Chiang arrives, we'll start the party.

• 下面是個不完整的句子，你知道問題出在哪裡嗎？
• Although she knew that it was dangerous. She walked home by herself.
  雖然她知道這是危險的，她還是獨自走回家。
• Although she knew that it was dangerous, she walked home by herself.
  雖然她知道這是危險的，她還是獨自走回家。

文法上有三種語氣：直述語氣、祈使語氣、假設語氣。最常見的假設語氣是以從屬連接詞 If 起頭的句子，用於表示願望、懷疑或假設。

假設語氣中，if 起頭的從屬子句，需要逗號 「,」隔開主要子句。若從屬子句在後面，則逗號可以省略。

If I study, I will pass the exams.
(= I will pass the exams if I study. )

如果我用功，我會通過考試。

If it rains, we'll have to stay at home.
(= We'll have to stay at home if it rains. )

如果下雨，我們將不得不留在家裡。

We apologize if this causes you any inconvenience.
(= If this causes you any inconvenience, we apologize. )

我們道歉，如果這會導致您的任何不便。