1. which 代替一个词

The government, which promises to cut taxes, will be popular. 这个政府，它保证要减税，将会是得人心的。

He is an excellent student in all subjects except for math, which is his shortcoming. 他是个除数学之外各科优秀的优等生，数学是他的短处。

2. which 代替一个短语

Every soldier was wearing earplugs, which made conversation difficult. 每位士兵都戴着耳塞，这便使会话变得困难起来。

They accused him of treating his mother badly, which of course he denied. 他们指责他与虐待母亲，当然，他对此断然否认。

3. which 代替一个句子

He got married again a year later, which surprised everybody. 他一年后又结婚了，这使大家都吃惊。

It was built in a year, which seems absolutely incredible. 它在一年内就建成了，这简直难以置信。

He began to try to sit up, which showed us that the effects of the drug were wearing off. 他开始试图坐起身来，这向我们表明药力正在消退。