句子的結構

3.定語從句
以從句的形式修飾或限定主句中的名詞、代詞、短語等的句子，叫作定語從句。
定語從句通常用關系詞(關系代詞和關系副詞)把它與主句連接起來。它在句中所修飾和限定 的>詞或短語稱為先行詞。
引導定語從句的關系代詞有：who(指人，在從句中作主語或賓語)，whom(指人，作賓語) ，whose(指人，作定語)，that(可指人或物)，which(指物)。
引導定語從句的關系副詞有：when(指時間)，where(指地點)，why(指原因)。這些關系副詞 相當于(介詞+which)。例如：
when=in(on，at，during)+which
where=in(at，to)+which
why=for which
(1)關系代詞在從句中作主語、表語、賓語或定語；關系副詞在從句中作狀語。
作主語：the woman who is talking to the teacher is her mother.
正在跟老師說話的那個女人是她的母親。
the boy who played the piano on the stage yesterday is mr. li's s on.
昨天在臺上彈鋼琴的那個男孩兒是李先生的兒子。
作定語：chaplin was a great actor whose name is well known all over the world.
卓別林是一位聞名于全世界的偉大的演員。
do you know the man whose son is your schoolmate?
你認識那個他的兒子是你同學的男人嗎?
作賓語：i am looking for the bike (that) i put here yesterday.)
我正在找昨天我放在這里的自行車。
these are the reference books (that) i bought for you yesterday.
這些是我昨天給你買的參考書。
作狀語：
指時間：
jack wasted much time on those days when he was in the middle school.
杰克上中學的時候，浪費了許多時光。
it was in 1937 when japanese soldiers broke into the city beiping.
日本鬼子闖入北平城是在一九三七年。
指地點：
this is the place where the composer beethoven was born.
這就是作曲家貝多芬出生的地方。
have you been to the seaside where we can enjoy swimming?
你去過那處我們可以盡情游泳的海濱嗎?
指原因：
do you know (the reason) why she was so sad?
你知道她為什么這樣傷心嗎?
who can tell me why it's so unfair?
誰能告訴我為什么老天爺如此不公平?
that's(the reason)why he was absent.
這就是他缺席的原因。
注意： ①當先行詞被first，last這類詞或最高級修飾時，一律都用that而不用which或who (不管 先行詞是指人還是物)。
this is the most beautiful picture that i have ever seen!
這是我所看見過的最美的畫!
i'm the only one that you can rely on.
我是你唯一能夠依靠的人。
②當先行詞為all，no，any，only，little，much，something，anything，nothing，everything等不定代詞的時候，必須用that作引導詞引導定語從句。
there is nothing that she can say to you.
她對你沒有什么話可說。
she is not interested in anything (that) he has told her.
她對他告訴她的任何事情都不感興趣。
(2)介詞前置的定語從句
關系代詞which和whom還可以作介詞的賓語，這時要把介詞放在整個定語從句的前面。
is this the school in which you studies?
(in which=where)
這是你上學的學校嗎?
the man on whom the whole family rely died in a traffic accident yesterday.