Can vs. May for Ability and Permission

Use can to talk about ability. Use can or may to ask for or give permission. “I can swim” describes what you’re able to do. “Can I sit here?” asks permission in ordinary conversation. “May I sit here?” asks the same question in a more formal tone.

Can vs. may at a glance

Use can to describe an ability

“Rosa can lift that suitcase” means she is able to lift it. “Can this printer handle envelopes?” asks about the printer’s capabilities. “Rosa may lift the suitcase” would mean she is allowed to lift it or that she might lift it, depending on the context.

A question with can can be read in different ways. A skills trainer asking “Can you drive the van?” may be checking ability. A colleague with full hands asking the same question is likely making a request. Write “Are you able to drive the van?” when the distinction matters.

Use can or may for permission

“Can I borrow your pen?” is a standard way to ask permission. “May I borrow your pen?” is more formal. Either question works. The person answering can say “Sure,” “Yes, you can,” or “Yes, you may,” depending on the setting. See Cambridge on asking for and giving permission.

When you ask for permission to do something yourself, start with “Can I” or “May I.” When you ask someone else to do something, “Can you” or “Could you” will often fit. “May I close the door?” asks permission for me to close it. “Could you close the door?” asks you to do it.

In rules or policies, may can state who is allowed to do something. “Staff may use the side entrance after 6 p.m.” clearly grants permission. In a sign that forbids parking, “No parking” makes the rule immediately clear. In conversation, “You can’t park here” can also state a prohibition.

Use context to distinguish types of possibility

“The trail can get muddy after rain” describes something that happens under some conditions. “The trail may be muddy right now” is a guess about this visit. For a specific uncertain event, may, might, or could often fits. For more examples, see May vs. Might.

Choose the verb by meaning first. If you’re describing ability, can is the usual choice. If you’re asking permission, think about the setting and the tone. When a sentence could suggest both, spell it out. “Maya is able to access the report” describes capability. “Maya is allowed to access the report” describes permission.

Practice choosing can and may

1. Which sentence directly describes Rae’s ability to read sheet music?

   1. Rae may read the sheet music during rehearsal.
   2. Rae might read the sheet music during rehearsal.
   3. May Rae read the sheet music during rehearsal?
   4. Rae can read sheet music.

2. Which pair shows two standard ways to ask permission to borrow a pen?

   1. “Can I borrow your pen?” and “May I borrow your pen?”
   2. “Can you lend me your pen?” and “May you lend me your pen?”
   3. “Can I to borrow your pen?” and “May I to borrow your pen?”
   4. “I can borrow your pen.” and “I may borrow your pen.”

3. Which sentence makes a general statement about what sometimes happens in winter?

   1. The bridge may be icy right now.
   2. The bridge might close this evening.
   3. The bridge can get icy in winter.
   4. Can I cross the bridge now?

4. Which sentence asks another person to move a chair?

   1. May I move your chair?
   2. Can you move your chair?
   3. May we move the chair?
   4. You may move your chair.

5. Which sentence gives formal permission in a library notice?

   1. Patrons might reserve a study room if one opens up.
   2. Can patrons reserve a study room?
   3. Patrons can reserve a study room, right?
   4. Patrons may reserve one study room per day.

For a chart of ability, permission, and other meanings expressed by helping verbs, see the guide to modal verbs.