1.定语从句的构成
n.+ 引导词+ 句子
2.定语从句的引导词
定语从句的引导词按照先行词的种类，一共分成五类：
1）人 who whom whose
2）物 that which whose
3）时间 that which when
4）地点 that which where
5）that which why
谁决定引导词的用法？
举例
• I will never forget the day (when) I met you（从句）.
that代词呢充当主语、宾语，从句啥都不缺
• I will never forget the day (that)we spent.
• You had better have some reason (why) you are late.
• You had better have some reason (taht) sounds perfect.
三类标准
1）代词 who whom that which(从句充当主谓宾)
2)副词 where when why(什么都不充当)
3）形容词 whose 修饰最近名词