Use may for permission. For example:
May she swim?
(Is she permitted to swim?)
Use can for ability. For example:
Can she swim?
(Is she able to swim?)
Can and May
There is often confusion over the words can and may.
Can
The word can is used to denote ability. For example:
-
- I can whistle.
(I have the ability to whistle.)
-
- Can he lift 150 kgs?
(Does he have the ability to lift 150 kgs?)
May
The word may is used to denote permission. For example:
-
- You may swim in this river.
(You are allowed to swim in this river.)
-
- May I have a biscuit?
(Am I permitted to have a biscuit?)
Can for Permission (Informal Setting)
These days, the word can is used for both ability and permission, particularly in an informal setting. For example:
-
- You can swim in this river.
(You are allowed to swim in this river.)
-
- Can I have a biscuit?
(Am I permitted to have a biscuit?)
Use May for Permission in a Formal Setting
If you have a reason to be «uber correct» (e.g., you’re hosting royalty or a very pedantic grandparent), you should use may to denote permission. For example:
-
- May I leave the table?
(Am I permitted to leave the table?)
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