定义

被动语态(passive voice)是动词的一种形式，用以说明主语与谓语动词之间的关系。英语的语态共有两种：主动语态和被动语态。主动语态表示主语是动作的执行者，被动语态表示主语是动作的承受者。被动语态是动词的一种特殊形式，一般来说，只有需要动作对象的及物动词才有被动语态。汉语往往用"被"、"受"、"给"等被动词来表示被动意义 。

被动句的构成

be +动词过去分词
例：English is spoken by many people.
英语被许多人讲。

五个基本句型的构成

①肯定句
Clothes are used for keeping warm.
衣服用来保暖。
②否定句
Clothes are not used for keeping warm.
衣服不是用来保暖。
③一般疑问句
Are clothes used for keeping warm?
衣服用来保暖吗？
④特殊疑问句
What are clothes used for?
衣服用来做什么？
⑤有情态动词的被动句
Clothes must be kept warm.
衣服必须保持温暖。

被动句的重要时态

①一般现在时/过去时
主动：People regard him as brilliant.
被动：He is regarded as brilliant by people.
人们认为他很有才华。
主动：The children gave the foreign guests a warm welcome.
被动：The foreign guests were given a warm welcome by the children.
孩子们热烈地欢迎外宾。
②完成时态
A. 现在完成时被动语气：have been done
主动：We have studied English for 3 years at the spare-time school.
被动：English has been studied by us for 3 years at the spare-time school.
我们已经在学校里学了三年英语了。
主动：They have set up a power station in their home town.
被动：A power station has been set up in their home town.
他们的家乡建立了一座发电站。
主动：People have piled plastic bags full of rubbish in streets.
被动： Plastic bags full of rubbish have been piled in streets.
人们把装满垃圾的塑料袋子堆放在街上。
主动：We have used nuclear energy to produce electricity.
被动：Nuclear energy has been used to produce electricity by us.
核能被我们用来发电。
主动：No one has ever beaten him at tennis.
被动：He has never been beaten at tennis.
就网球来说还没有人是他的对手。
B. 过去完成时被动语气：had been done
主动：Somebody had cleaned my shoes.
被动：My shoes had been cleaned by somebody.
有人已把我的鞋子擦了。
主动：They had built three ships by last December.
被动：By last December three ships had been built by them.
到去年年底他们已建造了三艘船。