てもいい (te mo ii)

Related patterns6

Similar

なくてもいい
てもいい permits doing something. なくてもいい permits not doing it, the opposite side.
放題ほうだい
てもいい gives permission for one thing, once (もう帰かえってもいい). 放題ほうだい grants no limit at all on how many times or how much (飲のみ放題ほうだい).
ても構かまわない
てもいい is the everyday choice, and can read eager. ても構かまわない lands cooler, and is the formal or business pick.

Opposite

てはいけないprohibition-vs-permission
も grants doing it ("may do"). は forbids it instead ("must not do").

Lookalikes

Same meaning1

may do; it's okay to

ても構かまわないit's fine to do; I don't mind if you doattaches at

All examples6

may do; it's okay to do — asking or granting permission

このパソコンは誰だれでも自由じゆうに使つかってもいい。
kono pasokon wa dare demo jiyuu ni tsukatte mo ii.
Anyone may use this computer. neutral
この傘かさ、借かりてもいい？
kono kasa, karite mo ii?
Can I borrow this umbrella? casual
写真しゃしんを撮とってもいいですか。
shashin o totte mo ii desu ka.
May I take a photo? neutral
こちらの資料しりょうは持もち帰かえってもよろしいでしょうか。
kochira no shiryou wa mochikaette mo yoroshii deshou ka.
Would it be alright if I took these materials home? formal

I don't mind doing it — volunteering an act nobody asked for

明日あしたでよければ、駅えきまで車くるまを出だしてもいいですよ。
ashita de yokereba, eki made kuruma o dashite mo ii desu yo.
If tomorrow works, I could drive you to the station. neutral
誰だれも行いかないなら、私わたしが行いってもいいよ。
dare mo ikanai nara, watashi ga itte mo ii yo.
If nobody else is going, I don't mind going. casual

How it's formed1

All forms6

ていいteiicontraction
味あじわっていい
も dropped in casual speech — 入はいっていい？
てもかまわないtemokamawanaiformal
味あじわってもかまわない
full entry at ても構かまわない — cooler and more detached than てもいい.
てもよろしいでしょうかtemoyoroshiideshoukaformal
味あじわってもよろしいでしょうか
keigo permission request toward superiors and customers

pastてもよかったtemoyokatta
味あじわってもよかった
politeてもいいですtemoiidesu
味あじわってもいいです
polite questionてもいいですかtemoiidesuka
味あじわってもいいですか

Notes

Granting permission needs the authority to grant it — permission flows
down, requests flow up. Volunteered upward, 手伝てつだってもいいですよ
reads as self-permission.