連詞用於引導從句以形成句子的一部分或修飾句子的構成要素的叫作從屬連詞.由從屬連詞所引導的句子叫從句。
連詞是連線單詞,短語,從句或句子的一種虛詞.
從屬連詞這種連詞是用以引導名詞性從句和狀語從句的.
在英語詞類中，連線詞可說是最容易掌握的一種。
從結構上說，英語連線詞分兩大類：並列連詞（coordinating conjunctions）和從屬連詞（subordinating conjunctions）。
並列連詞連線兩個或兩個以上地位平等的字、片語或分句。例如：(1) Air and water are indispensable to me.
(2) She likes going out with friends or playing outdoor games.
(3) Most workers have a good income, so they look very happy.
從屬連詞連線兩個或兩個以上的分句，形成複雜句中的從屬分句。例如：
(4) He said that he did not want to go .
(5) Many things have happened since I last saw him.
(6) You may come if you want to.
上述連詞的用法，看起來不難，但錯誤也難免。下面是些好例子：
(1) This book may be used both as a text as well as a reference book.
這裡的“as well as”和“both”不能搭配，應該將“as well ”改為“and”，使“both.......and......”變成關聯連詞（ correlative conjunction）
(2) He not only speaks Mandarin but also English.
這裡的“not only”應該移到“speaks”後面，使這個動詞兼顧兩個等立賓語：“Mandarin”和“English”。
(3) Although he is fat, but he is very weak.
英語裡的“although”和“but”是不見面的 ，因此這句裡的“ but”要去掉，不然“although”就要出來。
(4) Jim is not so strong like you.
這裡的“not so”必須和“as”連成一體；介詞“like”是不適宜的。
(5) No sooner had we reached our destination, they left.
"No sooner"必須和"than" 配成關聯連詞，把"than" 省掉是不對的，應該補上：
No sooner had we reached our destination than they left.
這句子的意思也可透過“as soon as”反映出來：
“As soon as we reached our destination, they left.”
(6) I took a taxi and which took me to the station.
這裡的並列連詞“and”是多餘的，必須去掉。如果要保留“and ”也可，但是形容詞分句裡的關係代詞“Which”要改成主語“it” ，使整個句子變成並列分句如下：
I took a taxi and it took me to the station.
(7) My friend came up to me and held my hand, said good-bye excitedly.
這裡的“and”應該用來連線最後兩個謂語才對：
My friend came up to me, held my hand, and said good-bye excitedly.
不然，就要把“said”改成“saying”。
My friend came up to me and held my hand, saying good-bye excitedly.
連詞用於引導從句以形成句子的一部分或修飾句子的構成要素的叫作從屬連詞.由從屬連詞所引導的句子叫從句。
連詞是連線單詞,短語,從句或句子的一種虛詞.
從屬連詞這種連詞是用以引導名詞性從句和狀語從句的.
在英語詞類中，連線詞可說是最容易掌握的一種。
從結構上說，英語連線詞分兩大類：並列連詞（coordinating conjunctions）和從屬連詞（subordinating conjunctions）。
並列連詞連線兩個或兩個以上地位平等的字、片語或分句。例如：(1) Air and water are indispensable to me.
(2) She likes going out with friends or playing outdoor games.
(3) Most workers have a good income, so they look very happy.
從屬連詞連線兩個或兩個以上的分句，形成複雜句中的從屬分句。例如：
(4) He said that he did not want to go .
(5) Many things have happened since I last saw him.
(6) You may come if you want to.
上述連詞的用法，看起來不難，但錯誤也難免。下面是些好例子：
(1) This book may be used both as a text as well as a reference book.
這裡的“as well as”和“both”不能搭配，應該將“as well ”改為“and”，使“both.......and......”變成關聯連詞（ correlative conjunction）
(2) He not only speaks Mandarin but also English.
這裡的“not only”應該移到“speaks”後面，使這個動詞兼顧兩個等立賓語：“Mandarin”和“English”。
(3) Although he is fat, but he is very weak.
英語裡的“although”和“but”是不見面的 ，因此這句裡的“ but”要去掉，不然“although”就要出來。
(4) Jim is not so strong like you.
這裡的“not so”必須和“as”連成一體；介詞“like”是不適宜的。
(5) No sooner had we reached our destination, they left.
"No sooner"必須和"than" 配成關聯連詞，把"than" 省掉是不對的，應該補上：
No sooner had we reached our destination than they left.
這句子的意思也可透過“as soon as”反映出來：
“As soon as we reached our destination, they left.”
(6) I took a taxi and which took me to the station.
這裡的並列連詞“and”是多餘的，必須去掉。如果要保留“and ”也可，但是形容詞分句裡的關係代詞“Which”要改成主語“it” ，使整個句子變成並列分句如下：
I took a taxi and it took me to the station.
(7) My friend came up to me and held my hand, said good-bye excitedly.
這裡的“and”應該用來連線最後兩個謂語才對：
My friend came up to me, held my hand, and said good-bye excitedly.
不然，就要把“said”改成“saying”。
My friend came up to me and held my hand, saying good-bye excitedly.