被动语态的构成
强调「被……」，把宾语提到前面当主语。
be + 过去分词（时态由 be 体现）
要点
- 被动语态表示主语是动作的承受者。
- 结构是「be + 过去分词」。
- 动作的执行者用 by 短语引出，常可省略。
- 只有及物动词才有被动语态。
- be 的形式只看主语，不受 by 短语里那个人影响：Two of the letters were written by him.（were 跟着 two）—— 就近与一致这一把尺在「主谓一致」那一类里。
- 过去分词那一栏要和不规则表一起记（make–made–made、write–wrote–written）：写成 was wrote 是把两栏混成了一栏 —— 记法与「动词时态」那几条相同。
- by 之外还有 with 与 in：说用的工具跟 with，说用的语言跟 in（原料另有 of / from，见本页那条提示），by 只接做事的那个人 —— The cake was cut with a knife. ／ The letter was written in French.
- 同一个"was + 分词形"有两条路，能不能补出 by 就是分界：He was taken（能补 by the police，是被动）对比 He was gone（补不出 by，说的只是状态）—— 别把这一类系表结构当被动去改。
例句
It is made of wood.
它是木头做的。
Paper was invented in China.
纸是中国发明的。
English is spoken in many countries.
英语在许多国家被使用。
The bridge was built last year.
这座桥是去年建的。
The whole room was lit with just two small lamps.
整间屋子只靠两盏小灯照亮。
Two of the windows were broken by the wind.
两扇窗被风吹破了。
易错提示
- be made of（看得出原料）／be made from（看不出原料）。
- 不及物动词（happen、take place）根本没有被动语态。
- 被动式前面那个 be 省不得：英语"被拆了"要说 was taken down，只写 taken down 就成了主动的过去式 —— 少一个 be 是这一格最常见的漏笔。
- by 也能表手段而不是执行者：The house is heated by solar power.（靠太阳能）—— 这一头的 by 后面没有人，别急着改成人称作主语的句子。