定语从句和同位语从句的区别一、 定语从句是形容词从句,其作用相当于一个形容词,是用来修饰前面的名词或代词的;同位语从句是名词从句,其作用相当于一个名词,是对前面的名词作进一步解释的。例如: 1 We heard the news that he had told her. 我们听到他对她说的消息。 2 We heard the news that he had won the game. 我们听到消息他赢得了比赛。 例1中的that从句的作用相当于一个形容词,其作用是修饰the news;例2中的that从句的作用相当于一个名词,是对the news的进一步说明。二、定语从句的引导词在从句中充当一定的成分,可作主语、宾语、状语等;而同位语从句中的引导词在从句只起连接作用,不作任何句子成分。例如: 1. A plane is a machine that can fly. 飞机是一种能飞的机器。 2. The fact that they didnt finish the work has to be faced. 必须面对事实,他们没有完成工作。