• Lucy does the homework in the evening.
The homework is done by Lucy in the evening.
• They often use computers in class.
Computers are often used by them in class.
They often use computers in class. Computers are often used by them in class.
They make these machines in Beijing. These machines are made in Beijing.
2.一般过去时的被动语态结构：
疑问词＋be＋主语＋过去分词＋ (by ~) English is studied by many students.
English is not studied by many students.
Is English studied by many students? Who is English studied by?
• They built the tall building last year.
The tall building was built by them last year.
• He took good care of his little brother yesterday.
His little brother was taken good care of by him yesterday.
• We make these machines in Beijing.
These machines are made in Beijing.
句式 肯定句：主语＋be + 过去分词＋(by ~)
否定句：主语＋be not ＋过去分词＋(by ~) 一般疑问句：Be ＋主语＋过去分词＋(by ~)? 特殊疑问句：
was/were +过去分词
1. They bought ten computers last term．
Ten computers were bought by them last term. 2.We planted many trees last year.
Many trees wer in that factory.
Shoes are made by them.
主变宾,宾变主, 谓动be done 时不变,人称、数、格随着变
• They play football on Sunday. Practice
Football is played by them on Sunday.
5.Rice is planted in South China.
6.He is said a good boy .
语态
语态：表示主语和谓语动词之间的关系。 英语有两种语态，即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。 如： Many students study English.(主动语态) English is studied by many students.
Practice
They play football on Sunday.
Football is played by them on Sunday. Lucy does the homework in the evening. The homework is done by Lucy in the evening.
(被动语态)
被动语态的结构
不同的时态有不同的被动语态结构
1.一般现在时的被动语态结构：
助动词be+及物动词的过去分词
助动词be有人称、数的变化,其变化规 则与be作为连系动词时一样。 如：The desk is made of wood.
The desks are made of wood. He is asked a question by the teacher.
1.Teenagers should be allowed to choose their own clothes.
2.English is spoken by many people .
3.The tickets about heroes are sold out .
4.Lucky 52 is watched on TV by many people .
1.Many students study English. English is studied by many students. 2.They make shoes in that factory. Shoes are made by themin that factory.
3.The teacher often asks him questions.
• We cleaned our classroom just now.
Our classroom was cleaned by us just now.
• They used this room for resting.
This room was used for resting by them.
He is asked questions by the teacher.
1.把主动语态的宾语变为被动语态的主语。 2.把主动语态的谓语变为被动语态的谓语。 3.把主动语态的主语变为被动语态的by
短语。（① by短语可以省。② by短语 后跟代词的宾格。）
主变被解题步骤
1. 找宾语 ----即动作的承受者 2. 判断宾语的单复数 ----即be动词的单复数. 3. 判断动词的时态 ----即be动词的时态. 4. 修改谓语的形式 ----即原句动词改为过去分词 5. 修改原句的主语 ----即by+ 宾语（原主语）.