被动语态（Passive Voice）：表示主语是动作的承受者，而不是动作的执行者。当我们不知道或不需要强调动作的执行者时，或者要强调动作的承受者时，常用被动语态。
主动语态：主语是动作的执行者，如：I clean the room.（我打扫房间）
被动语态：主语是动作的承受者，如：The room is cleaned by me.（房间被我打扫）
构成：be动词 + 过去分词（p.p.）
一般现在时被动：am/is/are + 过去分词
一般过去时被动：was/were + 过去分词
一般将来时被动：will be + 过去分词
含情态动词被动：情态动词 + be + 过去分词
by + 动作执行者（可省略）
主动变被动步骤：
1. 主动句的宾语变为被动句的主语
2. 主动句的谓语动词变为'be + 过去分词'
3. 主动句的主语变为by + 宾语（可省略）
The room is cleaned (by me).
The room was cleaned (by me).
The room will be cleaned (by me).
The room can be cleaned (by me).
使用被动语态的情况：
1. 不知道或不需要说明动作执行者
2. 强调动作的承受者
3. 动作执行者是泛指或显而易见
by后的动作执行者可以省略
be动词要根据主语和时态变化
注意过去分词的正确形式
某些动词短语的被动：look after → be looked after, take care of → be taken care of
否定式：be + not + 过去分词
疑问式：be + 主语 + 过去分词？
将主动句变为被动句： People speak English all over the world.
确定宾语作主语
💬 English作主语
动词变被动
💬 speak → is spoken（一般现在时，English是单数）
原主语变by短语
💬 by people（可省略，因为people泛指）
English is spoken all over the world (by people).
通过游戏掌握被动语态的转换
The classroom ___ by the students every day.
The bridge ___ two years ago.
The work ___ in two days.
将下列主动句改为被动句： 1. People grow rice in South China. Rice ___ in South China. 2. They built this house in 1990. This house ___ in 1990.
用括号内动词的被动形式填空： 1. English ___ (speak) by many people. 2. The book ___ (write) by him last year. 3. A new hospital ___ (build) next year.
将下列主动句改为被动句： 1. They speak Chinese in China. 2. We clean our classroom every day. 3. My mother bought me a new bike yesterday. 4. We will hold a sports meeting next week.