何时运用被动语态：

（1）强调动作的接受者：America was discovered by Columbus.
（2）不知谁是动作的执行者：You are wanted on the phone.
（3）作客观说明：It is said that the meeting has been put off. （经典句型）

主动变被动的基本方法：

（1）主动语态中的宾语变为被动语态的主语。
（2）谓语动词变为由“be + 过去分词”的形式，配合时态作相应变化。
（3）主动语态主语置于介词 by之后，如无必需，则省略。
（4）不及物动词没有被动语态。

现在  do (does) →am / is / are + done
We keep the piano in the living-room.
→The piano is kept in the living-room.

过去  did→was / were + done
They built the bridge in 1980.
→The bridge was built in 1980.

将来  will/shall do → will/shall + be + done
He will read the book tomorrow.
→The book will be read tomorrow.

现在完成  have/has done → have/has + been + done
We have delivered the newspaper.
→The newspapers have been delivered (by us).

过去完成  had done → had been done
She had seen the film before she came here.
→The film had been seen before she came here.

将来完成  will/shall have done → will/shall have + been + done
By the end of this term we shall have finished 80 texts.
→By the end of this term 80 texts will have been finished.

现在进行  am/is/are doing → am/is/are + being + done
They are drawing the picture.
→The picture is being drawn by them.< /p>

过去进行  was/were doing → was/were + being + done
He was reviewing their lessons at this moment yesterday.
→Their lessons were being reviewed at this moment yesterday.

情态动词   may                       may
              can                         can
              must                      must
             should      do   →     should      + be + done
             ought to                 ought to
             used to                   used to
You must write an article on the subject.
→An article must be written on the subject.

测试精编

1. Since the first space mission, many communication satellites ________.
A. was launched      B. are launched      C. have been launched      D. had been launched

2. What kind of advice ________ you?
A. has gave      B. was gave      C. had been given to     D. has given

3. The slave ________ from morning till night.
A. madeto work      B. was made working      C. was made worked      D. was made to work

4. The construction of the laboratory ________ by the end of July.
A. must be completing                 B. must complete
C. must have completed                D. must have been completed

5. Your proposal ________ by the committee soon.
A. is discussed                       B. has been discussed
C. is going to be discussed              D. will have been discussed

KEYS

1. C    2. C    3. D    4. D    5. C