名词性从句包括主语从句、宾语从句、表语从句和同位语从句.引导名词性从句的连接词按其在从句中所起的作用分为:
1)连接代词:who(-ever),what(-ever),which(-ever),whom(-ever),whose
2)连接副词:when,where,why,how
3)连接词:that,whether,if
词引导的定语从句
1.关系代词用来指代先行词是人或物的名词或代词
句子成分 用于限制从句或非限制性从句 只用于限制性从句
代替人 代替物 代替人或物
主语 Who which that
主语 Whom which that
宾语 Whose(=of whom) whose(=of which)
2.关系代词的用法
(1) 如果先行词是all,much,anything,something,nothing,everything,little,none等不定代词,关系代词一般只用that,不用which.例如:
All the people that are present burst into tears.
(2) 如果先等词被形容词最高级以及first,last,any,only,few,mush,no,some,very等词修饰,关系代词常用that,不用which,who,或whom.例如:
(3) 非限制性定语从句中,不能用关系代词that,作宾语用的关系代词也不能省略.例如:
There are about seven million people taking part in the election,most of whom、are well educated.
(4) which还有一种特殊用法,它可以引导从句修饰前面的整个主句,代替主句所表示的整体概念或部分概念.在这种从句中,which可以作主语,也可以作宾语或表语,多数情况下意思是与and this 相似,并可以指人.例如:
He succeeded in the competition,which made his parents very happy.
(5) that可指人或物,在从句中作表语,(指人作主语时多用who)仅用于限制性定语从句中.
(6) which可作表语,既可指人,以可指物.指人时,一般指从事某种职业或是有种特征.品性或才能的人.Which引导的定语从句可以限制性的,也可以是非限制性的.
(7) 如果作先作词的集体名词着眼于集体的整体,关系代词用which;若是指集体中的各个成员,则用who.
(8) 先行词有两个,一个指人,一个指物,关系代词应该用that.例如:
The boy and the dog that are in the picture are very lovely.
(9) 如果先行词是anyone,anybody,everyone,everybody,someone,somebody,关系代词应该用 who 或whom,不用 which.例如:
Is there anyone here who will go with you?
3.“介词+关系代词“是一个普遍使用的结构
(1) “介词+关系代词“可以引导限制性定语从句,也可以引导非限制性定语从句.“介词+关系代词“结构中的介词可以是 in,on,about,from,for,with,to at,of,without 等,关系代词只可用whom或 which,不可用 that .
(2) from where为“介词+关系副词“结构,但也可以引导定语从句.例如:
We stood at the top of the hill,from where we can see the town..
(3) 像listen to,look at,depend on,pay attention to,take care of等固定短语动词,在定语从句中一般不宜将介词与动词分开.例如:
This is the boy whom she has taken care of.
二.关系副词引导的定语从句
1.关系副词也可以引导定语从句
关系副词在从句中分别表示时间.地点或原因.关系副词when在从句中充当时间状语,where 充当地点状语,why充当原因状语.
2.that可引导定语从句表示时间.地点或原因
That有时可以代替关系副词 when,where 或者why引导定语从句表示时间.地点或原因,在 that引导的这种定语从句中,that也可以省去.