1 在定語從句中，被修飾的名詞或代詞稱為先行詞;引導定語從句的連接詞稱為關系詞, 其中that、which、who稱為關系代詞,where、when、how,why稱為關系副詞

2. 關系代詞who、whom 和whose指人,分別在從句中作主語、賓語和定語。which指物that多指物, 有時也指人,它們在從句中可以作主語或賓語。

定語從句中關系代詞作從句賓語時可以省略。

This is the thief (that/who/whom) we have been looking for these days. (這個就是我們近日一直在找的小偷。)

Please find a room which is big enough for all of us to live in. (請找一間足夠大能住下我們全體的房間。)

3. 關系代詞as

such + n + as … the same +n+ as …指物或整個句子.

These houses are sold at such a low price aspeopleexpected.

He is not the same man as he was (像 … 一樣的;像 … 之類;和 … 一樣)

4. 關系副詞。

when或where引導定語從句時,它們在從句中分別作時間狀語和地點狀語。

This is the room where they had a quarrel a week ago. (這是一個星期前他們吵架的房間。)

I can never forget the day when I first saw you. (我永遠不會忘記第一次見到你的日子。)

why 表示原因。在從句中用作原因狀語。

The reason why she is absent from school is that she was ill.

how 表示方式。在從句中用作方式狀語。

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