限定性定语从句与非限定性定语从句的区别 限制性定语从句 非限制性定语从句形式上 不用逗号和主句隔开 用逗号隔开意义上 是先行词不可缺少的定语，不能删除是对先行词的补充说明，删除后意思仍完整译法上 翻译成先行词的定语，“…的…” 通常翻译成主句的并列句关系词的使用 A ．做宾语时可省略 B ．可用 that A ．不可省 B
不用 that 非限制性定语丛句中 as , which 的区别1
which 引导非限制性定语丛句代表前面的整个句子的时候，一般是对主句的结果的说明eg
He grows too fast, which makes him taller than his classmates
as 引导非限制性丛句代表前面整个句子时一般来讲丛句的谓语动词有三种：A
含有 be 动词 He failed the exam, as is natural
实意动词的被动形式 As is reported, the fire caused a great loss
感官动词和意识类动词 如： see, hear, notice, know, learn,realize 等 As you know, I am a teacher
as 可翻译为正如 , 它引导的丛句可位于主句之前，也可位于主句之后 ; which 引导的该丛句只能位于主句之后
_________he realized, I was very useful to him
This elephant is like a snake, ________anybody can see
The sun gives us light and heat, ________makes the plant grow well
As (as) B
which C
