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 は、単に能力や適性を示すだけでなく、非常に基本的な言語ツールとして機能します。A1レベルの学習者にとって、can を理解することは、主にその依頼と許可（与える・拒否する）という2つの重要な機能に焦点を当てることです。これら2つの使い方は、英語での日常的な社会的やり取りにおいて不可欠であり、自分の必要を表現したり、相手の許容範囲を理解したりすることを可能にします。can は能力を示す場合 (I can speak English のように) もありますが、依頼や許可の用途は、コミュニケーションの異なる側面を扱います。何かを依頼するために can を使うとき、それは行動の許容性や物の利用可能性について尋ねていることになります。逆に、許可を与えるために can を使うときは、その行動が許されていることを明確に述べているのです。この説明では、これらの特定の用法を明確にし、日常の英語での自信を持った応用への強固な基盤を提供します。can を使いこなすことは、友人との会話、仕事の依頼、公共の場での質問など、さまざまな一般的な状況で、礼儀正しく効果的に関わるための手段を身につけることを意味します。Can は助動詞（modal verb）に分類されます。助動詞は、補助動詞、つまり「手助けする」動詞の一種です。助動詞は主要な動詞の前に来て、その動詞の意味を修飾し、可能性、義務、またはこの文脈では許可や依頼といったニュアンスを加えます。通常の動詞とは異なり、助動詞は初学者にとって簡単な、独自の文法特性を持っています。can の最も有益な特性の1つは、その不変性です。これは、主語が誰であっても can の形が変わらないことを意味します。主語が I、you、he、she、it、we、they のどれであっても、can という単語自体は決して変化しません。-s、-ed、-ing のような語尾を can に付けることは決してありません。これにより、活用が大幅に簡略化されます。例えば、文の構造は I can go、she can go、they can go のようになります。can の後には常に主要動詞の原形が続くということです。原形とは、動詞の最も単純な形であり、不定詞の to やその他の文法的な接尾辞が付いていないものです。例えば、can の後には eat を使う必要があり、to eat、eating、eats、ate ではありません。この厳格なルールは、すべての助動詞に普遍的に適用され、文の構築を予測可能で一貫したものにします。can のこれらの基本的な特性を理解することは、依頼や許可における正確な使用の基本となります。can は文の先頭に移動し、主語の前に来ます。例えば、You can help me という平叙文は、主語と助動詞を入れ替えることで質問 Can you help me? になります。このパターンは、can を含むすべての質問で一貫しています。can は not と直接結合して cannot またはその一般的な短縮形 can't を形成します。これらの形は、行動が許可されていないこと、または許可が拒否されたことを示します。主要動詞は、肯定文と同様に原形で続きます。例: You cannot go または You can't go。can のような助動詞が主要動詞の法（mood）を指定する言語原則を反映しています。can が依頼や許可を示すとき、それは単純な事実の陳述を、許容性についての問い合わせや、それについての宣言へと変えます。依頼や許可のような複雑な社会的機能を伝えるこの能力は、can を英語コミュニケーションの不可欠な一部にしています。can を使った文の形成は、明確でありながら非常に一貫したパターンに従います。これらの構造を習得することは、日常の英語のやり取りで文法的に正しく、社会的に適切な文を作成するための鍵となります。- 1依頼や許可を求める（質問）:
please がよく追加されます。Can + I / we + 動詞の原形 + (目的語/補語)? | Can I use your phone, please? | Can we order some food? | Can I sit here? |Can + I / we + have + (名詞句), please? | Can I have a glass of water, please? | Can we have the bill? | Can I have your attention? |Can I open the window?(窓を開けても良いか許可を求めている)Can we have the menu, please?(メニューをもらいたいと依頼している)Can I borrow your pen for a minute?(ペンを一時的に借りる許可を求めている)
can と主語の倒置（例: I can の代わりに Can I）は、助動詞を使った英語の質問形成の特徴です。I または we の後に常に動詞の原形を使用することを忘れないでください。- 1許可を与える（肯定文）:
主語 + can + 動詞の原形 + (目的語/補語). | You can go now. | You can use my laptop. | She can leave her bags here. |- `
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
| 使い方 | 形 | 例文（お願い） | 例文（許可） | 例文（拒否） |
|---|---|---|---|---|
|
何かを頼むとき
|
Can I/we + 動詞の原形 + ...?
|
Can I have a coffee?
|
-
|
-
|
|
何かをしてもいいか尋ねるとき
|
Can I/we + 動詞の原形 + ...?
|
Can I sit here?
|
-
|
-
|
|
許可を与えるとき
|
You can + 動詞の原形 + ...
|
-
|
You can use my pen.
|
-
|
|
許可を拒否するとき
|
You cannot/can't + 動詞の原形 + ...
|
-
|
-
|
You can't park here.
|
|
一般的な質問
|
Can + 主語 + 動詞の原形 + ...?
|
Can he help us?
|
-
|
-
|
フォーマル度スペクトル
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：依頼と許可
依頼
- Can I...? 何かをしてもいいか尋ねる
- Can we...? グループで尋ねる
許可
- You can... 許可を与える
- You can't... 許可を拒否する
主要ルール
- Base Verb 常に動詞の原形が続く
- No 'to' 決して「can to verb」ではない
Can：依頼 vs. 能力
「Can」を使った依頼/許可の流れ図
何かを頼みたいですか、それとも何かをする許可を求めたいですか？
許可を与えますか？
日常で使う「Can」の場面
コーヒーショップ
- • Can I have a latte?
- • You can sit over there.
友達と家族
- • Can I borrow your headphones?
- • You can use my car tonight.
公共の場所
- • Can I take a picture?
- • You can't park here.
オンライン/アプリ
- • Can I join your game?
- • You can download the update.
レベル別の例文
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?
間違えやすい
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.
よくある間違い
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?
文型パターン
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?
「Please」をつけよう！
「can」の後に「to」はいらない！
語尾の上がり方に注目！
状況が大事！
短い返事でもOK！
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.
発音
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.
暗記しよう
記憶術
CAN stands for: Considerate Asking Now.
視覚的連想
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
チャレンジ
Go to a local shop or a friend today and ask three questions starting with 'Can I...' or 'Can you...'.
文化メモ
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'.
会話のきっかけ
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?
日記のテーマ
よくある間違い
Test Yourself
___ I borrow your pen?
Find and fix the mistake:
Can I to use your phone?
Arrange the words in the correct order:
All words placed
Click words above to build the sentence
Score: /3
練習問題
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.
Choose the correct sentence:
We can't to go to the party.
Translate into English: 'Kann ich bitte hier sitzen?'
Arrange these words into a sentence:
Match the requests with their correct responses:
I'm sorry, you ___ smoke inside the building.
Which sentence is correct?
Translate into English: 'Du kannst das Fenster öffnen.'
Arrange these words into a question:
Can I going now?
Match the subject with the correct verb form:
Score: /12
よくある質問 (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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