用法：

作为代词：

（1）

Which is my workbook?

我的作业本是哪一本? （表示疑问）

（2）

He lives in the house which is opposite ours.

他住在我们对面的那栋房子里。(用做关系代词)

作为形容词：

（1）

Which university did you go to, Oxford or Cambridge?

你上过哪所大学?牛津还是剑桥? (用作疑问形容词)

（2）

The doctor told him to give up smoking, which advice he took.

医生叮嘱他戒烟,他接受了这一忠告。(用作关系形容词)

关系代词which有何用法

关系代词which在定语从句中通常只用于指事物，不用于指人。它在句子中主要用作主语或宾语。如：She was not on the train which arrived just now. 她不在刚才到达的那列火车上。(which在定语从句中用作主语)I’ve found the car keys which you were looking for. 你要找的汽车钥匙我找着了。(which在定语从句中用作宾语)关系代词which有时还可在定语从句中用作定语。如：He advised me to hide behind the door, which advice I took at once. 他劝我躲在门后，我立即照他的话做了。注意，关系代词which原则上只指物，不指人。但是，有时指的不是具体的某人，而是指某人的职业、身份、地位、职务、品质、特征等，此时要用which 而不用who。如：He talked like a scholar, which he was not. 他说起话来像个学者，其实他没什么学问。She talked like a native, which she hardly was. 她说起话来像是个本地人，其实她不见得是。They accused him of being a traitor, which he was. 他们指控他是叛徒，他真是叛徒。

定语从句中，which可以指代物体