● 連接詞是用來連接兩個詞彙、兩個片語或兩個句子的詞。
常見包含：and, but, ,or, so, because, when, if, before, after

● and、but 和 or 可用來連接句中個別的部分，and 是用來連接「同類型」的字。
My grandmother has two cats and two dogs.
(我奶奶有兩隻貓和兩隻狗。)
We have salty and sweet bread.
(我們有鹹的和甜的麵包。)

● but 用來表達「相反的概念」。
I went to his office, but he wasn't there.
(我到他的辦公室去，可是他不在。)
I tried to call him, but his voice mail kept picking up the call.
(我打電話給他，但一直轉到語音信箱。)

● or 用來表達「多者擇一」的可能性。
We could go on a vacation to Hong Kong or Macau.
(我們可以到香港或澳門度假。)
Are you married or single?
(你已婚還是單身？)

● because 用來描述「原因」，常連接子句。表示原因的子句會放在 because 後面。
I can't go because my wife won't let me.
(我不能去，因為我太太不讓我去。)
I can go because my wife is out of town.
(我可以去，因為我太太出城去了。)

● so 用來描述「結果或目的」，也是連接子句。表示結果或目的的子句會放在 so 的後面。
The meeting is cancelled, so you don't have to go now.
(會議取消，所以你現在不用去了。)
They want to meet you right now, so you have to come as soon as you can.
(他們想馬上見你，所以你得儘快趕來。)

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※ 本文節錄自《彩圖初級英文文法Let's See!【三版】（彩色16K+解答別冊）》
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[介紹] 英文簡單學 – 對等連接詞