透過連接詞，可以把兩個句子合併，並且清楚地表示前後兩句的關係。也就是說，善用連接詞可以讓句子的意思更清楚活潑、加強句子之間的關聯性，在寫作時，文章自然更流暢。
※ 以下內容節錄自貝塔語言出版新書《英文寫作高分指引 English Writing Guide》
連接詞分成兩大類，一種為「對等連接詞」，它所連接的前後句子地位平等，例如：and、or、but、so、for 等。另一種不對等的，就叫做「從屬連接詞」，它所連接的句子一主一從，例如：after、before、when、since、because、although、though、even though 等。
活用連接詞簡化句子的4 大重點
1「主動」的動詞，用現在分詞 (V-ing) 來簡化。
例：When I was a student, I often stayed up. 當我還是學生時，我常熬夜。
= Being a student, I often stayed up.
= When being a student, I often stayed up.（when 也可以保留）
2「被動」的動詞，用「過去分詞」來簡化。
= Being a student, I often stayed up.
= When being a student, I often stayed up.（when 也可以保留）
例：Because he was hit by a car, he stayed at the hospital for weeks.
因為被車撞，所以他住院好幾個星期。
= Hit by a car, he stayed at the hospital for weeks.（句首的 hit 是過去分詞）
因為被車撞，所以他住院好幾個星期。
= Hit by a car, he stayed at the hospital for weeks.（句首的 hit 是過去分詞）
3完成式也可以簡化，不管是主動或被動，只要把have / has / had 改成 having 即可。
例：Have / has / had + 過去分詞 → Having + 過去分詞
Since Peter had watched this movie before, he felt bored to watch it again.
→ Having watched this movie before, Peter felt bored to watch it again.
因為 Peter 之前已經看過這部電影，所以要他再看一次，他覺得相當無趣。
（當句子因為簡化而使名字消失時，要把下一句中的代名詞改回人名。）
Since Peter had watched this movie before, he felt bored to watch it again.
→ Having watched this movie before, Peter felt bored to watch it again.
因為 Peter 之前已經看過這部電影，所以要他再看一次，他覺得相當無趣。
（當句子因為簡化而使名字消失時，要把下一句中的代名詞改回人名。）
4否定句的簡化也非常容易，用 Not + V-ing 即可。
例：Because John didn’t want to hurt her feelings, he didn’t tell her the truth.
→ Not wanting to hurt her feelings, John didn’t tell her the truth.
因為不想傷了她的心，約翰沒跟她說實話。（John 為主詞）
→ Not wanting to hurt her feelings, John didn’t tell her the truth.
因為不想傷了她的心，約翰沒跟她說實話。（John 為主詞）
