2014年秋高中英语 Module 6 Animals in Danger 语法透析讲解外研版必修5
一、语意重复。定语从句的引导词在从句中都要充当一定的成分，所以从句里相应的句子成分不能再保留，否则就犯了语意重复的错误。如：
The main topic people a re often talking about at present is personal cars.
The main topic是先行词，关系代词that或which在从句中作宾语，被省略了，所以做宾语的替代词it不能再出现了。
二、分裂现象。如无特殊原因，定语从句应紧跟在先行词之后。如：
Everything that has weight and occupies space is called matter.
初学者很容易将此意表达成：Everything is called matter that has weight and occupies space. 这就是人为地造成的分裂现象。但是有时定语从句和先行词之间需要插入定语、状语或谓语时则另当别论。如：
There is an expression in his eyes that I cannot understand.先行词与定语从句之间被in his eyes隔开了。
三、主、谓不一致。当关系代词在从句中作主语时，从句的谓语动词应该和先行词的数与格保持一致，否则就是犯了主、谓不一致的错误。如：
God bless this ship and all that sail in her. (Bible)
本例先行词all指的是“所有的人”，所以定语从句的谓语不能用sails。
