第一课的小目标学完这一课，你要能做到三件事：① 根据把握程度选 must / might / can't；② 记住情态动词后永远接动词原形；③ 听力里听到 must be / might rain 能秒懂。
② 一图看懂全课（思维导图）
这张图就是本课的完整地图：情态推测 总共 5 大块，先有地图再走路，学起来不迷路。
情态推测 完整体系
→
把握梯度
must 一定
might/may 可能
could 也许
can't 不可能
→
后接原形
must be
might rain
can't be
→
推测现在
That must be...
He might be...
→
否定区别
might not 可能不
can't 不可能
→
PET 考点
听力推断
Part 5 完形
口语猜测
读法：从根出发，5 大块顺序走。每块下面是小节点，全记住你这一课就通关了。
③ 先认识它：推测动词怎么分把握
一句话：这四个情态动词不是"必须/可以"，而是"我有多大把握这么猜"。
Unit 4：That must be my dad — he always wears that jacket.（那一定是我爸——他总穿那件夹克）；It might rain later.（待会儿可能下雨）；That can't be the beach — there's no water!（那不可能是海滩——没有水！）。
为什么听力必考PET Listening 常考"根据线索推断"：听到描述一个人的穿着/行为，问"那是谁？"答案靠 must be / can't be 推出来。
might not ≠ can'tHe might not come. = 他可能不来（50% 不确定）；He can't come. = 他不可能来（几乎确定他来不了）。语气差很多。
从 KET 到 PET 的进阶提醒KET（A2）要求"能认出、能填对"；PET（B1）要求"会用、会说、会写"。同一个知识点，A2 只考单选，B1 还要你在 email 和口语里主动输出。所以这一课别停留在"看懂"，一定要把第 ⑧ΣA; 部分的句子大声说出来、写一遍。评分也更严：语法错一个、漏一个要点，写作分就往下掉一档。
④ 推测情态动词对照表
把握程度与用法
情态动词
把握
例句
must
一定（90%）
That must be my dad — he always wears that jacket.
might / may
可能（50%）
It might rain later. / We may go home.
could
也许（30%）
That could be the hotel, but I'm not sure.
can't
不可能（10%）
That can't be the beach — there's no water!
后接动词形式（死规则）
结构
例句
情态动词 + 动词原形
must be / might rain / can't be / could be
情态动词 + be + 形容词/名词
He must be tired. / She might be a doctor.
否定
might not / may not / can't（注意：must 表推测时否定用 can't，不用 mustn't）
must 表推测的否定是 can't，不是 mustn't肯定"一定是"用 must be；否定"一定不是/不可能"用 can't be。mustn't 是"禁止"，不是"不可能"。
⑤ 五类用法场景（配图记忆）
场景
例句
线索
1 根据强线索猜
You must be tired after the long journey.
长途旅行 = 一定累
2 不确定的预测
We might visit the museum tomorrow.
还没定
3 弱猜测
That could be the station over there.
看不太清
4 排除不可能
He can't be at school — it's Sunday!
周日 = 不可能在校
5 礼貌请求（may）
May I use your phone?（与推测无关，认识即可）
May I...? 礼貌请求
might 与 may 区别很小B1 阶段基本可互换：might 比 may 稍微更不确定一点点。考试里不考这个细微差别，会用即可。
⑥ 中国学生 5 大高频错误诊断
错误 1：情态动词后加 to ✗ It might to rain. → ✓ It might rain. 情态动词后永远动词原形，不加 to。
错误 2：第三人称加 s ✗ She mights come. → ✓ She might come. 情态动词不随人称变化。
错误 3：must 的否定用 mustn't ✗ That mustn't be the hotel. → ✓ That can't be the hotel. 表推测的否定是 can't；mustn't 是禁止。
错误 4：漏 be ✗ He must tired. → ✓ He must be tired. 后接形容词/名词时要加 be。
错误 5：might not 当 can't ✗ He might not be at school — it's Sunday!（表确定排除）→ ✓ He can't be at school. 几乎确定排除用 can't；might not 只是"可能不"。
⑦ PET 考点与真题演练
题型
怎么考
应对
Listening Part 2/3
听线索推断人物/地点
抓 must be / can't be 信号
Reading Part 5 完形
挖情态推测空
看线索强弱选把握程度
Speaking Part 3
讨论不确定的计划
We might... / It could...
Writing Part 6 email
给不确定的预测
It might rain, so bring an umbrella.
Reading Part 3
人物态度推断
must = 肯定；can't = 否定
真题风格演练（PET 出题方式）
真题风格 · PET Listening Part 2听到："The man is wearing a blue uniform and carrying a toolbox." 他最可能是？ A. a teacher B. a mechanic C. a doctor
B。toolbox（工具箱）+ 制服 → 一定是 mechanic。用 must be。
真题风格 · PET Reading Part 5 完形That (1) ______ be Sophie — she's on holiday in France! It (2) ______ be her sister. I'm not sure. It (3) ______ rain this afternoon, so take a jacket.
(1) can't（Sophie 在度假，不可能是她）；(2) could / might（不确定）；(3) might / may（可能下雨）。
真题风格 · PET Speaking Part 3你和搭档在讨论周末计划，你不确定下不下雨，怎么说？
参考：It might rain on Saturday. We could go to the museum instead, or we might go to the park if it's sunny.
考场提分提醒听力推断题：线索越确定越用 must/can't，线索模糊用 might/could。看到 must be 的否定空，别选 mustn't，选 can't。写作里给建议加个不确定预测（It might...），比绝对化更像 B1。
PET（B1）四部分速查
部分
时间
题量
与本课关系
Reading & Writing
1 小时 45 分
阅读 5 部分 + 写作 2 题
本课语法/词汇是 Part 5 完形与 Part 6 email 的得分点
Listening
约 12 分钟
4 部分，听两遍
抓本课信号词即可定位答案
Speaking
10-12 分钟
4 部分（含搭档）
本课背诵句直接用于 Part 2 独白与 Part 3 讨论
写作 Part 6 email 要求约 100 词、必须覆盖题目三个要点；口语 Part 2 个人独白约 1-2 分钟，Part 3 要和搭档互动（附和、提问、商量），不能各说各话。
3. That can't be the beach — no water! 那不可能是海滩——没水！
4. He must be tired after the trip. 旅行后他一定累了。
5. She might be at home. 她可能在家。
6. That could be the station. 那也许是车站。
7. He can't be serious! 他不可能是认真的！
8. We may go to the coast this weekend. 这周末我们可能去海边。
9. You must be hungry. 你一定饿了。
10. It might not work. 它可能不管用。
在旅途中做猜测（PET Speaking Part 2 · 讲一次旅行经历直接套）
Last summer we got lost. We saw a building and thought it (1) ______ be the hotel, but it (2) ______ — it was a hospital. A local person said the hotel (3) ______ be near the beach. We walked and found it at last. It (4) ______ be the best holiday we'd ever had!
ΣA; 口语练习：说出来才算会
PET Writing Part 1 email 万能开头/结尾（约 100 词三段式）开头：Hi Tom, thanks for your email — it was great to hear from you! 中间：题目给的三个要点，每个一句，用上本课语法/词汇。结尾：Write soon and tell me your news! Best wishes, Leo. 记住：三个要点缺一不可，否则扣分。
练习 A · 跟读（2 分钟）
跟着上面背诵卡读 3 遍：第一遍慢读看发音，第二遍正常速度，第三遍不看文字凭记忆说。
PET Speaking Part 2 个人独白万能开头/结尾（1-2 分钟）开头：I'd like to talk about... / The thing I want to tell you about is...；中间用 First of all... Also... But I think... 串两三个点；结尾：So, that's why I like it. Thank you for listening. 记住：别只说一句，要给例子、给理由，撑满 1 分钟。
练习 B · 自我对话（3 分钟）
Q: Whose bag is this? → A: It must be Anna's — it has her name on it.
Q: Is he at home? → A: He can't be at home — his car isn't here.
Q: Will it rain tomorrow? → A: It might, so take an umbrella.
练习 C · 挑战（2 分钟）
不用稿子，用 must / might / can't 各猜一次：猜猜外面天气、猜猜某人在哪、猜猜这个东西是谁的。
口语评分自查说完后对 3 条：① 后接动词原形了吗（might rain，不是 to rain）？② 后接形容词加 be 了吗（must be tired）？③ 推测否定用 can't 吗？
考场示范对话（读熟就能套）
Examiner: Look at this photo. Who do you think it is? You: It must be my mum — she's wearing her red jacket. It can't be my sister; she's much taller. Examiner: Where might they be? You: They might be at the beach. It could be Spain, but I'm not sure.