核心规则
被动语态的核心形式是 be + 过去分词，时态、情态和完成意义落在 be 及其前面的助动词上。主动句的宾语成为被动句主语，原主语只在必要时用 by 引出。
结构与例句
| 形式 | 例句 |
|---|---|
| 一般现在时 | The samples are tested daily. |
| 一般过去时 | The bridge was built in 2010. |
| 进行时 | The road is being repaired. |
| 完成时 | The work has been completed. |
| 情态动词 | The rule must be followed. |
使用场景
科学、新闻和正式说明常关注过程或结果而非执行者，因此常用被动。施事显而易见、未知、不重要或刻意不提时，可省略 by 短语。
常见错误
错误： The problem has solved. → 正确： The problem has been solved。
错误： The accident was happened yesterday. → happen 是不及物动词，不能构成被动，应写 The accident happened yesterday。
易混知识点
get + 过去分词 也可表示被动，语气较口语并常突出变化或意外：He got injured。过去分词作形容词则描述状态：The door is closed 可能表示门处于关闭状态。
总结
先确认动词能否带宾语，再按所需时态构造助动词链，最后判断施事是否值得说明。
高中 · 常见时态与情态动词的被动
高中学习重点
构造被动时先保留主动句的时态，再把主要动词改为过去分词：They check the equipment → The equipment is checked；They checked it → It was checked。情态结构为 情态动词 + be + done，否定词放在第一个助动词后。
双宾语动词常有两种被动：They gave us new instructions → We were given new instructions / New instructions were given to us。
小练习
- 改为被动：People use this method worldwide.
- 填空：The application must ___ (submit) before Friday.
- 改错：A new library will built next year.
参考答案
- This method is used worldwide。
be submitted。- 改为
will be built。
高中必修 · 进行、完成及短语动词的被动
进阶形式
进行时被动为 be being done：The system is being updated。完成时被动为 have been done：The results have been published。多个助动词出现时，最后保留 been/being + 过去分词，不要遗漏 be 的形式。
短语动词变被动时要保持整体：People have looked into the problem → The problem has been looked into。含宾补的结构要根据动词决定补语形式：They made him apologize → He was made to apologize。
小练习
- 填空：The old stadium ___ (replace) by a new one at present.
- 改为被动：They have put off the meeting.
- 改为被动：The teacher made the students rewrite the report.
参考答案
is being replaced。- The meeting has been put off。
- The students were made to rewrite the report。
选择性必修 · 报道结构与非谓语被动
语篇中的使用
报道动词常用两类被动：It is believed that the plan will work；The plan is believed to work。若报道的动作早于谓语时间，可用完成不定式：The scientist is believed to have discovered the method earlier。
非谓语也有被动：to be invited、being discussed、having been completed。选择时同时判断逻辑主语承受动作以及动作与主句的时间关系。正式写作不必为了显得客观而滥用被动；若施事重要且主动表达更清楚，应保留主动句。
小练习
- 改写：People say that the painting is over 500 years old.（以 The painting 开头）
- 填空：She was pleased ___ (invite) to the conference.
- 填空：___ (complete) ahead of schedule, the project received praise.
参考答案
- The painting is said to be over 500 years old。
to be invited。Having been completed。