連接詞分為并列連詞和從屬連詞。英文連接詞是連接英文單詞的詞，如also，and等。英語有486,000個左右的單詞，而連接詞卻只有70個左右，它們總是非常高頻率的出現在各類文章、對話、電郵等英語實際溝通中。
英文連接詞像膠水一樣將相關聯的句子連接起來，國際心理學家、語言學家、教育家Chris Lonsdale 龍飛虎又把它稱之為“膠水詞”。
下面讓我們來熟悉一下常用的英語連接詞包括哪些：
（1）表示承接的過渡詞：also,and,and then,too,in addition,furthermore,moreover,what's more,again,on top of that,another,first,second,third等.
（2）表示時間順序的過渡詞：
now,then,before,after,afterwards,earlier,later,immediately,soon,next,in
a few days,gradually,suddenly,finally··等.
（3）表示空間順序的過渡詞：near（to）,far（from）,
in front of,behind,beside,beyond,above,below,to the right/left,around,outside等.
（4）表示比較的過渡詞：in the same way,just like,just as等.
（5）表示轉折的過渡詞：but,still,yet,however,nevertheless,nonetheless,on the contrary,in spite of,even though等.
（6）一方面,另一方面：on the one hand,on the other hand,for one thing,for another等.
（7）表示結果和原因的過渡詞：because,since,so,as a result,therefore,then,thus,otherwise等.
（8）表示目的的過渡詞：for this reason,for this purpose,so that等.
（9）表示強調的過渡詞：in fact,indeed,surely,necessarily,certainly,without any doubt,truly,to repeat,above all,most important等.
（10）表示解釋說明的過渡詞：for example,in fact,in this case,for actually,for instance等.
（11）表示總結的過渡詞：in a word,above all,all in all,finally,at last,in conclusion,as I have shown,in another word,in brief,in short,in general,on the whole,as has been stated,last but not least等.
(12)表示轉折的過渡詞:But,However,Although / even though,Despite / despite the fact that,In spite of / in spite of the fact that,Nevertheless,Nonetheless,While,Whereas,Unlike,In theory… in practice