Requests & permission (can, could, may)

When you want someone to do something for you, or you want to be allowed to do something yourself, English often uses three small modal verbs: can, could and may. Can you help me? Could I borrow your pen? May I come in? (There are other polite forms too, such as Would you…?, but these three cover most everyday requests.)

All three work the same simple way. They are modals, so they never change their form, and the verb after them is always the plain base form — no to, no -s, no -ed. The real skill here is choosing the one that sounds right: can is friendly and direct, could is a little more polite, and may is the most formal.

Quick shortcut: to ask another person to act, use Can / Could you + base verb. To ask for permission, use Can / Could / May I (or we) + base verb.

(Could here is not a past tense — ✅ Could you wait? is a polite request about now, not about the past.)

Two things you can ask for

It helps to separate two very common situations:

In both cases the verb after the modal stays in its base form:

• ✅ Could you help me?, never ❌ Could you helps me?
• ✅ Can I have the bill?, never ❌ Can I to have the bill?

Asking someone to do something

To ask another person to do something for you, use Can you…? or, a little more politely, Could you…?:

• Can you pass the salt?
• Could you say that again, please?
• Could you help me with this bag?

Adding please makes any request warmer: Could you close the door, please? You can also soften a request with possibly: Could you possibly give me a hand?

Note that we use could you, not may you, to ask someone else to act: ✅ Could you help me?, never ❌ May you help me? (May is for asking permission, as below.)

Asking for permission

To ask whether you are allowed to do something, use Can I…?, Could I…? or May I…?. The same forms work with we, and you can ask permission for another person too:

• Can I use your phone?
• Could I ask you a question?
• May I leave early today?
• Could we wait here? · May my son come with us?

To ask for something — or for some information — the same patterns work with have:

• Can I have a glass of water?
• Could I have the menu, please?
• May I have your name, please?

All three are polite, but they are not quite equal:

• Can I…? — relaxed and friendly, fine with friends, family and most everyday situations.
• Could I…? — a little more polite and less direct; safe almost anywhere.
• May I…? — the most formal; common in writing, at work, or in polite service situations.

Good news: can, could and may do not change for he, she or it. Can she wait? Could she wait? May he come in? — never ❌ Could she waits?

Saying yes and no

For permission questions, replies often come back with can, even when the question used could or may:

• Could I open the window? — Yes, of course you can. / Sure, go ahead.
• May I sit here? — Yes, you may. / I'm sorry, this seat is taken.

Notice we don't usually reply with could: ✅ Yes, you can sounds natural, while ❌ Yes, you could does not.

When someone asks you to do something (a Could you…? request), you don't reply with can — you use a short phrase:

• Could you help me? — Sure. / Of course. / No problem. / Sorry, I can't right now.

A few natural ways to answer either kind:

• Yes: Of course. · Sure. · No problem. · Yes, you can. · Certainly. (formal)
• No: Sorry, you can't. · I'm afraid not. · Sorry, I'm using it.

A note on politeness

Less direct or more formal forms usually sound more polite: could sounds softer than can, and may sounds more formal still. With strangers, in shops and restaurants, or at work, Could I…? / Could you…? (with please) is usually a safe polite choice; May I…? is best in formal, official or very polite service situations. Among friends, can is perfectly polite and the most common.

For talking about what you are able to do rather than asking permission, see Be able to (ability). For rules and obligations — what you have to do — see Have to / must.

Common mistakes

• ❌ Could you to help me? → ✅ Could you help me? (no to after a modal)
• ❌ Can I to have the menu? → ✅ Can I have the menu? (base form, no to)
• ❌ May you open the door? → ✅ Could you open the door? (may asks permission; it isn't used to ask others to act)
• ❌ Do you can help me? → ✅ Can you help me? (modals make questions on their own — no do)
• ❌ Could she helps us? → ✅ Could she help us? (base form for every subject)
• Permission: Could I borrow your pen? — ❌ Yes, you could. → ✅ Yes, you can. (but a Could you…? request gets Sure / Of course, not can)

Quick check

Choose or complete the polite form:

1. ____ you pass me the salt, please? (friendly request to someone)
2. ____ I leave early today? (formal request for permission)
3. Could she ____ (helps) us with the bags? (fix the verb form)
4. Could I borrow your pen? — Yes, of course you ____.

Key takeaways

• Use Can / Could you + base verb to ask someone else to do something; use Can / Could / May I + base verb to ask permission for yourself.
• They are modals: the verb after them is always the base form (no to, no -s, no -ed), and the form is the same for every subject.
• Politeness rises from can (friendly) to could (more polite) to may (most formal) — and please makes any request warmer.
• Could here is a polite present request, not a past tense.
• May asks formal permission (especially with I/we, and for others: May he come in?) — but use could you, not may you, to ask someone to act.
• Answer permission questions with can (Yes, you can / Sorry, you can't); answer a Could you…? request with Sure / Of course.