她有两个弟弟，他们在这个城市工作。
1.I have a sister who works in a hospital. 我有一位在医院工作的姐姐。 （不只一位姐姐）
2. I have a sister, who works in a hospital. 我有一位姐姐，她在医院工作。（只有一位姐姐）
which/that which/that
which which
whose
whose
when
when 介词+which
where
where
why/for which for which
非限制性定从句还能将整个主句作为先行词，对 其进行修饰，常用which引导，这时从句谓语动 词用第三人称单数。
She seems not to have grasped what I meant, which upsets me.
Liquid water changes to vapor, which is called evaporation.
as 与 which
1. 两者均可引导非限制性定语从句，有时可以 互换。
The meeting was put off, which/as was exactly what we wanted.
观察比较
A: This is the house which we bought last month. He is the only one of the students that is good at French . Restrictive attributive clause(限制性定语从句)
4. as 引导的从句可以放在句首, as 本身有“正 如…..正象…”之意，与之连用的词有 know, see, expect, announce, point out 等。
e.g. As we all know, the earth is round.
as 引导的非限制性定语从句一些固定句型：
as 与 which
2. as,which引导非限制性定语从句时，都可以指代整个 主句，as引导的从句可位于句首，句末和句中，常译为 “正如”；which引导的从句只能位于句末，常译为“这， 那”。
He missed the show, which was a great pity. He invited me to dinner, which made me happy. As we all know, the Amber Room once belonged to Peter the Great.
The Amber Room once belonged to Peter the Great, as we all know.
as 与 which
3. 当与such或the same连用时，一般用as。 e.g. Such books as you tell me are
interesting. I have the same plan as you.
6．as we all can see 正如我们都会看到
的那样
整理一番
当我们做非限制性定语从句的练 习时，往往先确定先行词，然后 再分析先行词在从句中的成分， 再对关系词加以选择。
品读规律
Tom found the ancient book, which was broken.
先行词指物，在从 句中做主或宾语，
As is said in the newspaper, tw用o关f系ar词mwehrischs,aw the UFO in the field.as引导的非不限能制用t性hat Cindy is a lovely girl定, w语it从h w句h，om常位m于any people like to make friends.句首，which不可 I like the 介ho词us+e关,系wh代o以词se，windows face the sea. P29etoh先用pOl行关elyw词系m介 根 动il在词pl词 据 词ir从wce的 从 的mhG句o选句构eas做mm用的成e定be，谓。es语r可语wA，ausghuesltd8itnh,B2e0i0ji8n,gw. hen
限制性定语从句与非限制性定语从句的区别
意义
功能 形式
限制性定语从句 非限制性定语从句
与主句的语意关系紧凑， 与主句的语意关系松散， 定语从句不能去掉，否则 定语从句能去掉 意思不完整
对先行词进行修饰
对先行词进行附加说明
无逗号与主句隔开
有逗号与主句隔开
品味一“翻”
她有两个在这个城市工作的弟弟。 She has two brothers who are working in the city. She has two brothers, who are working in the city.
注意1：有时同一个限制性从句变为非限制 性定语从句会改变全句的意思。
非限制性定语从句 先行词+，+关系词+句子
She has two brothers, （who are working3;,+ 关系代词 + 从句
Now teenagers like to go to the fast food restaurants, (where eating doesn't take much time).
B: The house, which we bought last month, is very nice. Harry is our monitor, whose mother is our maths teacher. Non-restrictive attributive clause(非限制性定语从句)
1．as has been said before 如上所述
2．as may be imagined 正如可以想象出
来的那样
3．as is well known
众所周知
4．as was expected
正如预料的那样
5．as has been already pointed out
正如已经指出的那样
结构： 先行词 +,+ 关系副词 + 从句
关系词t的ip 区t别ha:t，why不能在非限制性定语从句中使用。
先行词
人
物
人/物 时间 地点 原因
关系词在句 中所作的成 分
主语 宾语 主语 宾语
定语
时间状语
地点状语 原因状语
限制性定语 非限制性定
从句
语从句
who/that
who
whom/who/that whom