Grammar Rule in 30 Seconds
Use 'can' to ask for permission or make requests without changing the verb for different people.
- Use 'Can I...?' to ask for permission, like 'Can I go now?'
- Use 'Can you...?' to ask someone to do something, like 'Can you help?'
- Never add '-s' or 'to' after 'can', like 'He can swim' (not 'He cans to swim').
Overview
can 这个词是英语里最亲民、最简单的词之一。它就像是我们中文里的“万金油”，在很多场合都能派上用场。can 的第一印象是“能”或者“会”，比如 I can swim（我会游泳）。但在日常社交中，can 还有一个极其重要的功能，那就是用来表达请求（Requests）和询问/给予许可（Permission）。简单来说，就是当你想要别人帮你做点什么，或者你想问问能不能做某件事时，can 就是你的最佳拍档。can，不仅能让你表达清楚意图，还能让你显得非常有礼貌。这不仅仅是学语法，更是在学习如何用英语进行得体的社交。这节课，我们就来彻底搞定 can 在“请求”和“许可”这两个场景下的用法。你会发现，这真的比你想象中要简单得多！can 被归类为 Modal Verb（情态动词）。别被这个专业的术语吓跑了，你可以把它理解为一种“辅助性”的动词。它自己不能独立撑起一个句子，必须站在另一个动词的前面，给那个动词加上一点“态度”或“色彩”。can 的用法其实非常符合我们的直觉，因为它有几个超级棒的特点：- 1它永远不变形（Invariance）：
can 也是一样！在英语中，大部分动词会根据主语变来变去（比如 I eat 但 He eats），但是 can 非常佛系。无论主语是 I, you, he, she, it, we 还是 they，它永远都是 can。没有 cans，没有 canning，也没有 canned。这种“以不变应万变”的特质，对初学者来说简直是福音。- 1后面直接跟动词原形（Base Form）：
can 的时候，它后面的那个动作必须保持最原始的样子。你不需要在中间加 to，也不需要给后面的动词加 -ing。比如“我可以走吗？”，就是 Can I go?，而不是 Can I to go?。这和中文的“我能走吗？”结构几乎一模一样。- 1疑问句只需“大挪移”：
can 的时候，你只需要把 can 提到句子的最前面，和主语交换一下位置，一个请求或询问许可的句子就诞生了。- 1否定形式很直接：
can 后面加 not。在口语中，我们最常用的是它的缩写形式 can't。这就像中文里的“不能”或“不可以”。Can + 主语 (I / we) + 动词原形 + (其他信息) + please?Can I use your pen, please? | 我可以用一下你的笔吗？ | 加 please 更礼貌 |Can I have a cup of water? | 我可以要杯水吗？ | 餐厅常用句式 |Can we sit here? | 我们能坐这儿吗？ | 询问空位 |Can you help me? | 你能帮帮我吗？ | 请求他人协助 |Can you... 是请求别人做事，而 Can I... 是请求自己做事，但在 A1 阶段，它们都属于 can 的请求范畴。can + 动词原形 + (其他信息).You can go home now. | 你现在可以回家了。 |You can use my computer. | 你可以用我的电脑。 |You can try this cake. | 你可以尝尝这个蛋糕。 |can't (或 cannot) + 动词原形 + (其他信息).No, you can't. | 不，你不行。 | 直接但略显生硬 |You can't smoke here. | 你不能在这儿抽烟。 | 陈述规则 |I'm sorry, you can't park here. | 抱歉，你不能停在这儿。 | 加上 sorry 更好 |can 的这两种功能（请求与许可）具体在哪些时候用呢？让我们带入一些充满生活气息的场景。Give me milk tea，会显得非常没礼貌。这时候，can 就派上用场了：Can I have a pearl milk tea, please?(麻烦给我一杯珍珠奶茶。)Can I get the bill?(我可以买单吗？/ 麻烦结账。)
Can I sit here?(我可以坐这里吗？) —— 比如在拥挤的地铁上看到一个空位。Can I take a photo?(我可以拍照吗？) —— 在博物馆或艺术展厅。
can 能帮你优雅地提出请求：Can I borrow your charger?(我能借下你的充电宝吗？)Can you send me the file on WeChat?(你能把那个文件在微信上发给我吗？)You can use my umbrella.(你可以用我的伞。) —— 当你看到朋友没带伞时，主动给予许可。
You can't bring food into the library.(你不能带食物进图书馆。)Sorry, you can't enter without a mask.(抱歉，不戴口罩不能进入。)
Do this 或 Give me that）通常只用于关系非常亲密的家人或紧急情况。对于陌生人、服务人员或同事，使用 Can I... 或 Can you... 是一种基本的社交礼仪。它把“命令”变成了“询问”，给了对方选择的余地，这在英语思维里是非常重要的“面子”工程。can 很简单，但受中文习惯的影响，中国学习者常会掉进以下几个坑里：to (The to Trap)to（比如 want to, need to, hope to），导致很多同学顺口就说出了 Can I to...。- 错误：
Can I to borrow your book?(❌) - 正确：
Can I borrow your book?(✅) - 老师解析： 记住，
can是情态动词，它非常有“霸气”，不需要to这个中介，直接跟动词原形。这和中文“我能借”的结构是一致的，中文里也没有多余的词，所以请放心大胆地去掉to。
can 乱变形 (The Conjugation Error)he 或 she 就想给 can 也加个 s。- 错误：
She cans enter the room.(❌) - 正确：
She can enter the room.(✅) - 老师解析：
can是个“不老男神/女神”，它永远不会变老（加ed），也不会变多（加s）。无论主语是谁，它永远是can。请把它当成一个固定的符号来记。
please 导致语气太硬Can I have water? 语法没错，但在英语国家，如果不加 please，听起来会像是在下命令，而不是请求。- 建议： 养成在
Can I...句末加please的习惯。这就像在中文里说话前先说个“请问”或者句尾加个“麻烦了”，会让你的交流顺滑很多。
can 的否定形式 cannot 必须连写成一个单词，不能写成 can not（虽然有时可见，但不常用且不规范）。而在口语中，请务必练习 can't 的发音，注意那个末尾的 t 声音要轻但要有。can 的不同面貌以及它和“邻居”们的区别做个对比。can 表示“能力” vs. can 表示“许可/请求”I can speak English. | 能力 (Ability) | 描述你会的一项技能 |Can I speak now? | 许可 (Permission) | 询问现在是否轮到你发言 |He can run fast. | 能力 (Ability) | 描述他的身体素质 |Can he come in? | 许可 (Permission) | 询问他是否被允许进来 |Can vs. May (进阶对比)May I...。它和 Can I... 有什么区别呢？Can I...? | May I...? |can 就足够应付 90% 的日常生活场景了。may 听起来非常考究，如果你在麦当劳点餐用 May I have a burger?，虽然没错，但会显得过于严肃。can 吗？有没有更礼貌的说法？can 是最基础的。如果你想更礼貌一点，可以把 can 换成 could。比如 Could you help me?。这就像是把“你能帮我吗？”变成了“请问您能帮我吗？”。但在初学阶段，先把 can 用熟是最重要的。Can I sit here?，我该怎么回答？- 如果同意：
Yes, you can.或者更地道的Sure!/Of course!/Go ahead. - 如果不同意：
I'm sorry, you can't. This seat is taken.(抱歉，不行。这里有人了。)
can 和 can't 的发音听起来很像，怎么区分？can 通常发得很轻、很快（听起来像 kun），而 can't 的元音发得比较饱满，且末尾有一个明显的停顿或轻微的 t 音。在听力中，如果你听到一个词被重读且语气坚决，那通常是 can't。I can to play?to 的原形。你可以想象 can 是一个大磁铁，它直接把动词吸过来了，中间容不下 to 这个小零件。can 的请求和许可用法，是你通往地道英语口语的第一步。记住：不变形、不加 to、变疑问往前挪。下次去咖啡厅或者想借东西时，试着大胆地说出一句 Can I... 吧！你会发现，英语交流其实可以像发个微信朋友圈一样简单自然。加油！Conjugation of 'Can' (Permission/Requests)
| Subject | Affirmative | Negative | Question |
|---|---|---|---|
|
I
|
I can
|
I can't / cannot
|
Can I...?
|
|
You
|
You can
|
You can't / cannot
|
Can you...?
|
|
He/She/It
|
He/She/It can
|
He/She/It can't / cannot
|
Can he/she/it...?
|
|
We
|
We can
|
We can't / cannot
|
Can we...?
|
|
They
|
They can
|
They can't / cannot
|
Can they...?
|
Contractions
| Full Form | Contraction | Usage Note |
|---|---|---|
|
cannot
|
can't
|
Most common in speech
|
|
can not
|
n/a
|
Rare, used for extreme emphasis
|
Meanings
A modal verb used to express that something is allowed (permission) or to ask someone to perform an action (request).
Asking for Permission
To ask if you are allowed to do something in an informal or neutral setting.
“Can I sit here?”
“Can we watch TV?”
Giving Permission
To tell someone they are allowed to do something.
“You can use my pen.”
“You can go home early today.”
Making Requests
To ask someone else to do something for you.
“Can you pass the salt?”
“Can you call me later?”
Offering Help
To ask if the speaker can do something for someone else.
“Can I help you?”
“Can I carry your bag?”
Reference Table
| 用法 | 句式结构 | 请求示例 | 许可示例 | 拒绝示例 |
|---|---|---|---|---|
|
想要某样东西
|
Can I/we + 动词原形 + ...?
|
Can I have a coffee?
|
-
|
-
|
|
请求做某事
|
Can I/we + 动词原形 + ...?
|
Can I sit here?
|
-
|
-
|
|
给予许可
|
You can + 动词原形 + ...
|
-
|
You can use my pen.
|
-
|
|
拒绝许可
|
You cannot/can't + 动词原形 + ...
|
-
|
-
|
You can't park here.
|
|
一般疑问句
|
Can + 主语 + 动词原形 + ...?
|
Can he help us?
|
-
|
-
|
正式程度
May I have a glass of water, please? (Socializing)
Can I have a glass of water? (Socializing)
Can I grab some water? (Socializing)
Can I get a splash? (Socializing)
Can：请求与许可
请求
- Can I...? Asking to do something
- Can we...? Asking for group
许可
- You can... Giving permission
- You can't... Refusing permission
核心规则
- 动词原形 Always follow with base verb
- 不加 'to' Never 'can to verb'
Can：请求 vs. 能力
如何使用 'Can' 进行请求/许可
你想请求某物或请求做某事吗？
你要给予许可吗？
日常使用 'Can' 的场景
咖啡馆
- • Can I have a latte?
- • You can sit over there.
亲友之间
- • Can I borrow your headphones?
- • You can use my car tonight.
公共场所
- • Can I take a picture?
- • You can't park here.
网络/APP
- • Can I join your game?
- • You can download the update.
按水平分级的例句
Can I have a glass of water?
Can you help me, please?
You can sit here.
Can I use your pen?
Can we go to the park?
Can I take your coat?
You can't use your phone in the exam.
Can you tell me the time?
Can I pay by credit card?
We can't stay very long.
Can I just check something with you?
Can you make sure the door is locked?
You can leave your bags at the reception.
Can I ask why you are late?
Can you give me a hand with this box?
Can I have your attention for a moment?
Can you believe we've been here for three hours?
You can't expect me to finish this by tomorrow.
Can I get back to you on that later?
Can you possibly lend me ten dollars?
Can I just interject there for a second?
Can we not just agree to disagree?
How can you be so sure about the results?
Can I take it that you're in agreement?
Can you imagine the fallout if this fails?
Can I but hope that my efforts were not in vain?
Can one truly justify such a radical shift in policy?
Can we perhaps entertain the notion of a compromise?
Can you at all conceive of a scenario where this works?
Can I be of any further assistance to your lordship?
容易混淆
Many learners think they are interchangeable, but 'may' is strictly for formal permission.
Learners don't know when to switch to 'could'.
Learners use 'be able to' for permission.
常见错误
He cans help you.
He can help you.
Can I to go?
Can I go?
Do you can help?
Can you help?
I no can come.
I can't come.
I can to play.
I can play.
Can you for me help?
Can you help me?
I wonder if can I go.
I wonder if I can go.
Can it be that he is late?
Could it be that he is late?
句型
Can I have ___?
Can you ___ me?
Can I ___ here?
Can we ___ later?
Can you tell me ___?
Real World Usage
Can u call me?
Can I have a latte?
Can you send me that file?
Can you tell me where the station is?
Can I have a blanket?
Can we talk about this outfit?!
Can I ask about the team culture?
Can I take this medicine with food?
加上 'Please'！
Can I have a tea, please?
别在 'can' 后加 'to'
Can I go?，千万别说 Can I to go?。
注意语调上扬
Can I sit here?
看场合使用
Could I ask a question?
短句回答也 OK
Yes, you can. 既简单又自然。Smart Tips
Add 'possibly' or 'please' to the sentence.
Remember: 'Can' is a superhero; it doesn't need the 'Do' sidekick.
Use 'I'm afraid' before 'you can't' to be softer.
Just say 'Can I?' while reaching for the object.
发音
The Weak 'Can'
In affirmative sentences, 'can' is usually unstressed and sounds like /kən/ (kun).
The Strong 'Can't'
The negative 'can't' is always stressed and has a long vowel /kænt/ or /kɑːnt/.
Rising Intonation
Can I go? ↗
Shows it is a polite question.
记住它
记忆技巧
CAN stands for: Considerate Asking Now.
视觉联想
Imagine a bright green 'Go' light. When you ask 'Can I?', you are waiting for that green light to move forward.
Rhyme
To ask for a thing or a place to be, start with 'Can' and you'll be free!
Story
Little Charlie wanted a cookie. He didn't say 'Give me cookie.' He said, 'Can I have a cookie?' His mom smiled and said, 'Yes, you can!'
Word Web
挑战
Go to a local shop or a friend today and ask three questions starting with 'Can I...' or 'Can you...'.
文化笔记
British speakers often use 'Could' more than 'Can' to avoid appearing too direct or rude.
American speakers are generally more direct and use 'Can' frequently in all but the most formal settings.
Very informal; 'Can' is standard, often paired with 'mate'.
From the Old English word 'cunnan', which meant 'to know' or 'to know how to'.
对话开场白
Can you tell me about your favorite hobby?
Can I ask what you did last weekend?
Can you recommend a good movie?
Can we talk about your plans for the future?
Can you explain the plot of the last book you read?
日记主题
常见错误
Test Yourself
___ I borrow your pen?
Can 用于请求许可。Am 和 Do 在这里不符合语法。Find and fix the mistake:
Can I to use your phone?
can 后面，我们直接用动词原形，不需要 to。Arrange the words in the correct order:
All words placed
Click words above to build the sentence
Can + 主语 + 动词原形 + 宾语 + ?Score: /3
练习题
8 exercisesI'm sorry, you ___ park here. It's for doctors only.
___ I use your phone?
Find and fix the mistake:
He cans help you with your bags.
you / salt / pass / can / the / ?
1. Can I have the bill? | 2. Can I see your passport? | 3. Can you pass the remote?
¿Puedo entrar? (Spanish)
You want to ask a stranger for the time.
A: Can I sit here? B: Yes, you ___.
Score: /8
Practice Bank
12 exercisesYou ___ park your car here.
选择正确的句子：
We can't to go to the party.
将这句话翻译成英语：'我可以坐在这吗？'
将单词排序：
将请求与对应的回答连线：
I'm sorry, you ___ smoke inside the building.
哪句话是正确的？
翻译成英语：'你可以打开窗户。'
将单词排序组成问句：
Can I going now?
将主语与正确的 can 用法连线：
Score: /12
常见问题 (8)
Yes. While some traditionalists prefer `may`, `can` is standard and correct in modern English for permission.
`Can` is for permission/ability; `can't` is the negative form (cannot).
It's better to use `could` or `may` in a formal email to sound more professional.
Because `can` is a modal verb, and modal verbs never change their ending.
No, it's a request. It's a polite way to ask someone to do something.
In American English, it's like `kant` (rhymes with pant). In British English, it's often `kahnt`.
No. Never use `to` after `can`. Just say `Can I go?`.
Use `could` when you want to be extra polite or when asking a stranger for a favor.
Scaffolded Practice
1
2
3
4
Mastery Progress
Needs Practice
Improving
Strong
Mastered
In Other Languages
Poder
English 'can' does not conjugate for person.
Pouvoir
English uses inversion (Can I?) instead of a question phrase.
Können / Dürfen
English 'can' covers both ability and permission.
~te mo ii desu ka
Japanese uses a sentence ending, English uses a helper verb.
Yumkin (يمكن)
Arabic often uses a prefix or a separate verb for ability vs. permission.
Kěyǐ (可以)
English changes word order for questions; Chinese does not.
Learning Path
Prerequisites
Learn These First
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