🎯 这节课你会学到
- 什么时候用被动（主语是被动作打到的一方）
- 万能公式 be + 过去分词，六种时态的被动全推导
- 情态动词的被动
📖 讲解
1. 什么时候用被动？
主动句：人们 speak Chinese.（人们说中文——主语是动作执行者） 被动句：Chinese is spoken by people.（中文被人们说——主语是承受者）
两种情况用被动：
- 不知道 / 不必说谁干的：The bridge was built in 1990.（谁建的不知道/不重要）
- 强调承受者：English is spoken all over the world.（强调英语）
2. 万能公式：be + 过去分词
被动 = be 动词承担「时态和人称」+ 实义动词变过去分词。be 变、分词不变：
| 时态 | 主动 | 被动 |
|---|---|---|
| 一般现在 | make / makes | am / is / are made |
| 一般过去 | made | was / were made |
| 一般将来 | will make | will be made |
| 现在进行 | is making | is being made |
| 现在完成 | has made | has been made |
| 情态动词 | can make | can be made |
推导方法（不用死背表）：先按正常时态写 be（is/was/will be/has been…），后面一律跟过去分词。
例句走一遍：
- 一般现在：Rice is grown in the south.（水稻种植在南方）
- 一般过去：The bridge was built in 1990.
- 将来：A new school will be built here next year.
- 完成时：The work has been finished already.
- 情态：The book can be borrowed from the library.
3. by 短语（要说「被谁」时）
被动句里执行者用 by 引出：The letter was written by Tom.（这封信是汤姆写的）
不想说谁干的 → by 短语直接省略（考试里大多数被动句都不带 by）。
4. 判断主动还是被动的信号词
- 主语是物 + 及物动词 → 八成是被动：The room is cleaned every day.
- 时间 + 地点 + 及物动词（无宾语）→ 被动：The meeting was held in Beijing last year.
⚠️ 零基础最容易犯的错
- 漏 be：❌ The room cleaned every day. → ✅ The room is cleaned every day.（be 是被动的心脏）
- be 后用了过去式：❌ was built→had built 混淆 → be 后一律分词：was built ✓（build-built-built 三态同形是特例，注意 went→gone 这类才是真错：❌ was went）
- 主动被动颠倒：看到主语是物 + 无宾语，还写主动 → 逐题问「主语是干这个的吗？」
📝 随堂小练
- Chinese ____ (speak) by more and more people now.
- The sports meeting ____ (hold) last week.
- A new hospital ____ (build) here next year.
- The work ____ already ____ (finish).（完成时被动）
- Books ____ (can / borrow) from the library.（情态被动）
答案（先自己写！）
- is spoken（一般现在被动；Chinese 三单 → is）
- was held（last week → 过去被动；hold-holded ❌ → held 不规则）
- will be built（将来被动 = will be + 分词）
- has already been finished（完成时被动 = has been + 分词）
- can be borrowed（情态 + be + 分词）
➡️ 下一课预告
第 11 课：比较级与最高级——「更」「最」在英语里怎么变。