人教版高中英语选择性必修第一册知识点(25)

as said before 正如之前所说的那样
③. 使用非限制性定语从句时的注意事项
(1)that不能引导非限制性定语从句。在非限制性定语从句中，用who, whom指代人，用which指代物。
Mr Smith, who is my friend, resigned last year. 史密斯先生是我的朋友，他去年辞职了。
(2)当先行词是专有名词或被物主代词、指示代词修饰时，其后的定语从句通常是非限制性定语从句。
This is my videophone, which was bought yesterday.
这是我的可视电话，是昨天买的。
(3)非限制性定语从句可以补充说明整个主句。
He is shallow, which is known to us all in our company.
他很肤浅，我们公司的人都知道。
(4)非限制性定语从句表原因时，不用why引导,而用for which代替why。
We could not give the reason, for which so many people were in favour of the draft. 我们无法解释，为什么这么多人支持这项草案。
(5)先行词是独一无二的事物时，一般用非限制性定语从句修饰。
The sun, which rises in the east, gives us light and heat.
太阳从东方升起,给我们带来光和热。
④. 关系代词、人称代词、指示代词的选择
关键是判断句子结构：
非限制性定语从句→选关系代词
并列句→选人称代词或指示代词
He has three sons, none of whom is an architect. (定语从句)
他有三个儿子，没有一个是建筑师。
He has three sons, but none of them is an architect. (并列句)
他有三个儿子，但没有一个是建筑师。
He has three sons, who are architects. (定语从句)
他有三个儿子，他们是建筑师。