一、被动语态概述
语态是动词的一种形式，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，一般说来，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"等词来表示被动意义。
如：
He opened the door.他打开了这扇门。（主动语态）
The door was opened.这扇门被打开了。（被动语态）
二、被动语态的构成
被动语态由"助动词be+及物动词的过去分词"构成。被动语态的时态变化只改变be的形式，过去分词部分不变。疑问式和否定式的变化也如此。
1、被动语态的时态较常见的八种，现以动词clean为例列表说明：
2、被动语态的句式变化：
以一般现在时和动词invite为例，列表说明被动语态的句式变化：
3、含有情态动词的被动语态
情态动词的被动语态结构为：情态动词+be+过去分词；其时态及句型的变化仅由情态动词完成，"be+过去分词"部分不变。如：
Tables can be made of stone.桌子可由石头制造。
Tables could be made of stone at that time. 那时桌子可由石头制造。（一般过去时）
Can tables be made of stone? 桌子能用石头制造吗？（疑问句）
三、主动语态变为被动语态
转换图示：
1、主动语态变为被动语态的步骤：
（1）将主动句的宾语变为主语：
注意：如果主动句的宾语是代词，需将其由宾格变为主格。如：
Tom killed him. → He was killed by Tom.
（2）将动词改为"be+过去分词"。
注意：They held a meeting yesterday. → A meeting was held by them yesterday.他们昨天开会了。
（3）将主动语态的主语改为be…放在谓语动词后。
注意：如果原主语是代词，则应由主格变为宾格。
He sang a song. → A song was sung by him.
2、主动语态变为被动语态的注意事项：
含有双宾语，即直接宾语（常指事物）和间接宾语（常指人）的句子，每个宾语都可变为被动语态的主语，即其被动语态有两种形式。但多以间接宾语作主语。
Jack told us the truth.杰克告诉了我们真相。
We were told the truth by Jack.
The truth was told (to) us by Jack.
四、动词的主动形式表示被动之意
系动词无被动语态：以主动形式表示被动之意
常见的系动词有：
① be动词
② ……起来（7个）：look/seem/appear, feel(感觉，摸起来), sound, smell, taste
e.g. She seems/appears happy. It smells terrible.
③ (逐渐)变得/变成：become, grow, get, turn, come, go
e.g. His wish has come true.
People often went hungry in the old days.
The tree is growing tall.
④ 保持：keep, stay
e.g. We must keep quiet in the reading room.
五、下列动词（词组）没有被动式：
1、happen, take place, break out, belong to ,cost, take
2、不及物动词sell, wash, read , write, open, close, shut, lock, wear等，常用主动形式表示被动意义。
○1、An accident was happened yesterday.（×）昨天发生了一起事故。
An accident happened yesterday.
○2、The flower smells sweet.这花闻起来很香。
○3、The watch looks good.这表看起来很好。
○4、This book sells well.这本书畅销。
○5、The kind of cloth washes well. 这种布很容易洗。
○6、The article reads well. 这篇文章读起来很好。
○7、The supermarket opens at 8:00 in the morning. 超市在早上八点钟营业。
○8、The door won't close/shut. 这门关不上。
○9、The door locks easily. 这门容易锁。
○10、This material wears well (won't wear). 这种材料耐久（不耐久）
望采纳！！ 谢谢！！！
