英语语法: 被动语态(被动句)
被动语态
英语语态有两种：主动语态和被动语态
兔子咬人啦！“兔子”是重点
谁被兔子咬了？“谁”是重点
主动语态强调动作的执行者
被动语态强调动作的承受者
被动语态的构成也是通过谓语动词的变化完成的。
构成：be+动词过去分词。
如果需要表明动作的执行者是谁，应该用 by+动作执行者。
被动语态的基本知识：五种基本句型的被动语态。
1. 主+谓 【没有被动语态】
The rabbit slept.
不存在动作承受者，自然没有被动语态。
2. 主+谓+宾
The rabbit ate the carrot. 兔子吃了胡萝卜。
The rabbit：动作ate的执行者
The carrot：动作ate的承受者
变成被动语态就是强调动作的承受者，让the carrot成为主语，所以首先要调换主语、宾语的位置
->the carrot ate the rabbit.
->变成被动语态 the carrot is eaten the rabbit. be动词应该用is的过去时态was
-> the carrot was eaten the rabbit.
如果需要表明动作的执行者是谁，应该用 by+动作执行者。
->the carrot was eaten by the rabbit. 胡萝卜被兔子吃了。
这个句子写的简洁一点：A carrot was eaten.
【非谓语动词：过去分词作主语补语（表语）
The rabbit was frightened (by the wolf). 兔子感到害怕
The rabbit was frightening. 兔子令人感到害怕
所以过去分词表被动的意义和被动语态脱不了干系】
3. 主+谓+宾+宾
The rabbit gave the carrot（直接宾语） to the wolf（间接宾语）. 兔子给了狼胡萝卜
The wolf was given the carrot by the rabbit. 狼被兔子给了胡萝卜。（强调间接宾语）
The carrot was given to the wolf by the rabbit. 胡萝卜被兔子给了狼。（强调直接宾语）
The rabbit gave the wolf（间接宾语） the carrot（直接宾语）. 兔子给了狼胡萝卜
The wolf was given the carrot by the rabbit. 狼被兔子给了胡萝卜。（强调间接宾语）
The carrot was given to the wolf by the rabbit. 胡萝卜被兔子给了狼。（强调直接宾语）
4. 主+谓+宾+宾补
The wolf invited the rabbit to her party. 狼邀请了兔子去她的聚会。
The rabbit was invited to the party by the wolf.兔子被狼邀请去了聚会。
*注意
The rabbit made the wolf to laugh. 兔子把狼弄笑了。
Make后边接的是省略to的不定式，这种不带to的动词不定式被称为bare infinitive
这种省略了to的动词不定式改成被动语态时，要把to还原。
The wolf was made to laugh by the rabbit. 狼被兔子逗笑了。
5. 主+系+表（主语补语）【没有被动语态】
The rabbit is smart.
这种句型没有办法变成被动语态。
被动语态和时态、语气、情态动词相结合的话，就会产生一系列“化学反应”，比如：
The rabbit has eaten the carrot.
The carrot has been eaten by the rabbit.
The carrot has not been eaten by the rabbit.
Has the carrot been eaten by the rabbit.
The rabbit would have eaten the carrot.
The carrot would have been eaten by the rabbit.
The carrot would not have been eaten by the rabbit.
Would the carrot have been eaten by the carrot.
The rabbit might eat the carrot.
The carrot might be eaten by the rabbit.
The carrot might not be eaten by the rabbit.
Might the carrot be eaten by the rabbit.
这些变位主要是针对构成被动语态所需的be动词的变位，很有规律。
