第1个回答 2011-11-18
取决于先行词在定语从句中的位置,当先行词在定从中作主语就用作主语的关系代词,当先行词在定从中作宾语时关系代词就作宾语
eg this is the book that i need. i need the book. 先行词做need的宾语,所以此句关系代词就宾语。
i need a book which is about cultural diffenence. a book is about cultural diffenence. book 作主语。所以 which作主语。