N4Grammar

といい

I hope, I wish, You should, It would be good

Structure

Verb + と + いい
［い］Adjective + と + いい
［な］Adjective + だ + と + いい
Noun + だ + と + いい

Wishing for others:
(Desired Outcome) Phrase + といい + ね

Wishing for oneself:
(Desired Outcome) Phrase + といい + なぁ
(Desired Outcome) Phrase + といい+んだ⁽¹⁾ + けど⁽²⁾

⁽¹⁾ のだ
⁽²⁾ けれど、けども、けれども、が

Explanation

The particle と, when used to convey 'if', indicates that the outcome is a natural or certain result. By pairing it with the い-Adjective いい, it creates the meaning 'it would be good if (A)'.

This grammar pattern can attach to the end of any phrase, as long as the final word is in its plain form.

今夜(こんや)は料理(りょうり)したくないな～、外食(がいしょく)するといいな。
I don't feel like cooking tonight. It'd be nice if we ate out.
明日(あした)の旅行(りょこう)は楽(たの)しいといいね！
I hope your trip tomorrow is a lot of fun!
天気(てんき)予報(よほう)が本当(ほんとう)だといいね！
I really hope the weather forecast is right!
「次(つぎ)の誕生日(たんじょうび)プレゼントはゲームだといいな～」と息子(むすこ)が言(い)っていました。
My son was saying, 'I hope my next birthday present is a video game'.

Due to the nuance of certainty that と provides, this grammar pattern expresses a strong desire. Consequently, といい is often more naturally translated as 'I hope (A)' or 'I wish (A)'.

This structure can be used to express a wish for yourself or for another person. The sentence-ending particle typically clarifies this distinction: な or んだけど is used for one's own hopes, while ね is used when wishing for others or sharing a wish.

バスで席(せき)に座(すわ)れるといいな。
I hope I can get a seat on the bus. (Hoping for your own benefit)
試験(しけん)に合格(ごうかく)するといいんだけど、全然(ぜんぜん)勉強(べんきょう)していないから無理(むり)かも。
I'd love to pass the exam, but since I haven't studied at all, it might be impossible. (Hoping for your own benefit)
新(あたら)しい仕事(しごと)がうまく行(い)くといいね。
I hope your new job goes well for you. (Hoping for another's benefit)

Caution

Finishing this pattern with conjunctions like けど, けれども, or が adds a nuance that some circumstances may prevent the speaker's wish from coming true.

あの店(みせ)がまだ開(あ)いているといいんだけど。（もう遅(おそ)いから閉(し)まっているかもしれない）
I hope that shop is still open. (But it's already late, so it might be closed)
給料(きゅうりょう)が上(あ)がるといいんだが。（会社(かいしゃ)の業績(ぎょうせき)が悪(わる)いから難(むずか)しいだろう）
It would be nice to get a raise. (But since the company's performance is bad, it's probably unlikely)

Examples

試験(しけん)に合格(ごうかく)するといいですね。

I hope you pass the exam.

健康(けんこう)のために、毎日(まいにち)運動(うんどう)するといいです。

You should exercise every day for your health.

この料理(りょうり)、美味(おい)しいといいんですが。

I hope this dish is delicious.

いつか夢(ゆめ)が叶(かな)うといい。

I hope my dream comes true someday.

早(はや)く病気(びょうき)が治(なお)るといいね。

I hope you get well soon.

週末(しゅうまつ)はピクニックだから、雨(あめ)が降(ふ)らないといいね。

We're having a picnic this weekend, so I hope it doesn't rain.

急(いそ)ごう！終電(しゅうでん)に間(ま)に合(あ)うといいね。

Let's hurry! I hope we can make the last train.

今度(こんど)のホテルは静(しず)かだといいなぁ。

I hope the next hotel is quiet.

分(わ)からないことがあったら、先生(せんせい)に聞(き)くといい。

If there's something you don't understand, you should ask the teacher.

卒業(そつぎょう)しても、またみんなで会(あ)えるといいね。

I hope we can all meet again even after we graduate.

まだ時間(じかん)はあるから、あのお店(みせ)が開(あ)いているといいね。

There's still time, so I hope that store is still open.

旅行(りょこう)の日(ひ)、晴(は)れだといいのだが。

I really hope it's clear on the day of our trip.