外观
情态动词（推测）
约 514 字大约 2 分钟
2026-04-05
情态动词（推测）
表达对事情可能性的判断。按语气从强到弱排列。
中考频率：⭐⭐⭐ 高频。must（肯定推测）和 can't（否定推测）是语法选择必考点，may/might 常在阅读理解中表示作者不确定的态度。
推测语气强度
| 语气 | 情态动词 | 含义 | 示例 |
|---|---|---|---|
| 最肯定 | must | 一定、肯定（90%+） | He must be at home. 他一定在家。 |
| 较肯定 | will / would | 会 | That will be Tom. 那会是 Tom。 |
| 可能 | should / ought to | 应该 | He should be here soon. 他应该快到了。 |
| 不确定 | may / might | 可能（30-50%） | She may know the answer. 她可能知道答案。 |
| 不肯定 | could | 有可能 | It could be true. 这有可能是真的。 |
| 不可能 | can't / couldn't | 不可能 | It can't be true. 这不可能是真的。 |
三类推测结构
1. 对现在的推测
| 结构 | 示例 |
|---|---|
| must do | He must be tired now. |
| may do | She may be at the library. |
| can't do | He can't be a teacher. |
2. 对正在进行的推测
| 结构 | 示例 |
|---|---|
| must be doing | She must be sleeping now. |
| may be doing | He may be waiting for us. |
3. 对过去的推测
| 结构 | 示例 |
|---|---|
| must have done | He must have left already. |
| may have done | She may have forgotten. |
| can't have done | He can't have said that. |
高频辨析
| 对比 | 用法 |
|---|---|
| must vs can't | 肯定推测→must；否定推测→can't（不是 mustn't！） |
| may vs might | might 可能性更低，也可表过去推测 |
| must 推测 vs must 必须 | 看上下文：The light is on. He must be home.（推测） |
⚠️ mustn't 不用于推测！ mustn't = "禁止"。
反意疑问句
| 陈述句 | 反意疑问 |
|---|---|
| He must be a teacher, | isn't he? |
| He must have finished, | hasn't he? |
| He must have gone yesterday, | didn't he?（有过去时间→用 did） |
考点速查
| 考试题型 | 常见考点 |
|---|---|
| 语法选择 | must（肯定推测）vs can't（否定推测）；must have done |
| 阅读理解 | may/might 表示作者不确定的态度 |
| 选词填空 | 情态动词 + 动词原形 |