Japanese Grammar

Asking for Permission: 〜てもいい

To ask 'May I...?' or 'Is it okay if I...?', Japanese uses the ~te mo ii form. It literally translates to 'Even if I do this, is it good?'

How to Ask and Give Permission

In English, we say 'May I open the window?' or 'You may sit here'. In Japanese, we attach 'mo ii' (also good) to the Te-form of the verb.

If you make it a question (〜てもいいですか?), you are asking for permission.

If you state it as a fact (〜てもいいです), you are giving permission to someone else.

You can also use this with the negative form (〜なくてもいい) to say 'You don't have to...'.

Conjugation Rules

Asking for Permission (May I...?)
Te-form
Te-form + もいいですか (mo ii desu ka)
Is it okay even if I...?
食べる (taberu)
食べてもいいですか? (Tabete mo ii desu ka?)
May I eat?
座る (suwaru)
座ってもいいですか? (Suwatte mo ii desu ka?)
May I sit?
Giving Permission (You may...)
Te-form
Te-form + もいいです (mo ii desu)
It is okay even if you...
帰る (kaeru)
帰ってもいいです。 (Kaette mo ii desu.)
You may go home.
No need to... (You don't have to...)
Nai-form
Drop 'i', add くてもいい (kutemo ii)
Is it okay even if I don't...?
行かない (ikanai)
行かなくてもいいです。 (Ikanakute mo ii desu.)
You don't have to go.

Example Sentences

写真を撮ってもいいですか。
Shashin o totte mo ii desu ka.
May I take a picture?
ここに座ってもいいですよ。
Koko ni suwatte mo ii desu yo.
You may sit here. (Giving permission)
明日、来なくてもいいです。
Ashita, konakute mo ii desu.
You don't have to come tomorrow.

Teacher's Advice

How to say 'No'

If someone asks 'Tabete mo ii desu ka?' (May I eat?), how do you say no? Saying 'Iie, tabete mo ii ja arimasen' is WRONG! To deny permission, you must use the 'must not' grammar: '~te wa ikemasen'. So say: 'Iie, tabete wa ikemasen' (No, you must not eat).

JLPT Exam Patterns

  • Choosing the correct response to a ~te mo ii question in listening sections (N5)
  • The opposite of ~te mo ii (You may) is ~te wa ikemasen (You must not) (N5)
  • Understanding ~nakutemo ii (You don't have to) (N5)

Frequently Asked Questions

What does 〜てもいい mean?

〜てもいい literally means "even if you do X, it is good" — in practice, "you may / it's okay to." As a question (〜てもいいですか), it asks for permission: 入ってもいいですか ("May I come in?"). It attaches to the te-form of the verb.

How do you say something is NOT allowed in Japanese?

The negative answer to 〜てもいいですか is not 〜てもいいじゃない. Use 〜てはいけません ("you must not") or the softer 〜ないでください ("please don't"). For example: ここでタバコを吸ってはいけません.

What is the difference between 〜てもいい and 〜なくてもいい?

〜てもいい gives permission to do something, while 〜なくてもいい says something is not necessary: 行かなくてもいい means "you don't have to go." The JLPT often tests this pair together, so learn them as a set.

Related Grammar

Master Permissions

Practice asking for and giving permission in various situations.