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N5Lesson notes · Oct 4, 2026

Open in Japanese: 開あける vs 開あく, ひらく, 営業中えいぎょうちゅう, and 心こころを開ひらく

"To open" in Japanese has two main verbs. 開あける (あける) is when you open something: ドアを開あける, "open the door". 開あく (あく) describes something opening, without saying who or what causes it: ドアが開あく, "the door opens". The same kanji read ひらく is for things that open out, like books, umbrellas, hands and flowers, and for holding events like meetings. A shop's "Open" sign usually says 営業中えいぎょうちゅう (えいぎょうちゅう).

Learners get stuck on this pair first, and then on ひらく, which works with both を and が. This post gives you a picture for each verb, the shop signs you will see on the street, and the lines you will hear in anime.

How do you say "open" in Japanese?

What is the difference between 開あける and 開あく?

開あける (あける) is transitive: it names the thing being opened, with を. 開あく (あく) is intransitive: it names the thing that opens, with が, and does not say who did it. These are the basic forms; in the potential form 開あけられる, the thing being opened can take が or を.

窓まどを開あけてください。 — Please open the window. (polite) ドアが開あいた。 — The door opened. (casual, read あいた)

The core picture for あける / あく is a gap appearing in something that was closed: a door, a window, a box, your eyes, your mouth. That is why you say 目めをあける and 口くちをあける, and why a dentist says 口くちを開あけてください ("please open your mouth"). For more pairs like this, see transitive and intransitive verbs.

How do you say "it is open"?

開ひらいている (あいている) is "it is open", a state. 窓まどが開あいている is "the window is open".

窓まどが開あいているよ。 — The window's open. (casual, read あいている)

The opposite pair is 閉しめる (しめる, to close something) and 閉しまる (しまる, to close). 閉しまっている (しまっている) means "it is closed", a state.

When is 開ひらく read ひらく?

開ひらく read ひらく often suggests opening out, as with books, umbrellas, fans, hands and buds. It is also used for doors, starting businesses and holding meetings. It works with both を and が, so it is transitive and intransitive at once.

教科書きょうかしょの10ページを開ひらいてください。 — Please open your textbooks to page 10. (polite, in class, read ひらいて) 傘かさを開ひらいた。 — I opened my umbrella. (casual, read ひらいた) チューリップのつぼみが開ひらいた。 — The tulip bud opened. (casual, read ひらいた)

The first two sentences name the thing being opened, so they take を. The third names the thing that opens, so it takes が. For flowers, 咲さく (さく) is the usual verb for a bloom report, as in 桜さくらが咲さいた. 開ひらく describes the petals or bud opening out, as in バラのつぼみが開ひらいた ("the rose bud opened"), compared with バラが咲さいた ("the rose bloomed").

To open a meeting or an event, ひらく is also used: 来週らいしゅう、会議かいぎを開ひらきます (らいしゅう、かいぎをひらきます) is "We will hold a meeting next week". The opposite of ひらく is 閉とじる (とじる): 本ほんを閉とじる, "close a book", and ファイルを閉とじる, "close a file".

How do you say a shop is open?

What does 営業中えいぎょうちゅう mean?

営業中えいぎょうちゅう (えいぎょうちゅう), "open for business", is the "Open" sign on shops. 準備中じゅんびちゅう (じゅんびちゅう) means "preparing", closed for now.

On the street you will also see two older-style signs. Wooden signs hung outside ramen shops and izakaya often say 商あきない中なか (あきないちゅう) for open and 仕度したく中なか (したくちゅう) for "getting ready, not open yet". They mean the same as 営業中えいぎょうちゅう and 準備中じゅんびちゅう, but many learners have never met them.

この店みせは何時なんじまで開あいていますか? — Until what time is this shop open? (polite)

In conversation, people often ask 何時なんじまでやっていますか? ("What time do you close?") instead. It is just as polite and very common.

What does オープン mean?

オープン is used for a new shop's opening, 新あたらしくオープンしたカフェ, and also for a shop's daily opening time: 十時とときにオープンします, "we open at ten".

駅前えきまえに新あたらしいカフェがオープンした。 — A new cafe opened in front of the station. (casual)

For "the shop is open right now", 開ひらいている and 営業中えいぎょうちゅう are the basic words.

Which similar words get mixed up with あける?

These words look alike and get mixed up. Here they are side by side.

Word Reading Meaning Example
開あける あける to open (something) 箱はこを開あける
開あく あく to open 自動じどうドアが開あく
開ひらく ひらく to open out (book, umbrella, bud), to hold (a meeting) 傘かさを開ひらく
空あける あける to make empty or free 金曜日きんようびを空あける
空あく あく to be empty or free 席せきが空あいている
閉しめる しめる to close (something) カーテンを閉しめる
閉しまる しまる to close ドアが閉しまる
閉とじる とじる to close (book, file) 本ほんを閉とじる
営業中えいぎょうちゅう えいぎょうちゅう open for business 営業中えいぎょうちゅうの看板かんばん
オープン オープン opening; opening for business 新あたらしくオープン

The two あける that trip people up are 開あける and 空あける. 席せきを空あける means "to leave a seat empty", for example for someone else, and 予定よていを空あける means "to clear your schedule". To keep something free for later, add おく: 席せきを空あけておく. Same sound, different kanji, and 空あける has nothing to do with a door.

The basic verbs above are for beginners; we have also introduced expressions used on shop signs. The sections below go a step further.

What do you hear in anime and conversation?

Anime gives you the breakdown cases quickly. When a character is stuck behind a door, you hear ドアが開ひらかない! ("the door won't open!"). When someone is outside knocking, you hear 開あけて! ("open up!"), or the rough 開あけろ!. 開あけろ is a strong command. Outside of fiction or jokes, do not use it for ordinary requests. The fairy-tale line "Open Sesame" is 開あけゴマ (ひらけごま) in Japanese, and there 開あけ is read ひらけ, the command form of ひらく.

The pair also shows up as 開ひらかない versus 開あけられない. ドアが開ひらかない states the fact that the door does not open. ドアが開あけられない says that you cannot open it, whatever the reason: a lock, a fault or a lack of strength.

Beyond the basics

What does 心こころを開ひらく mean?

心こころを開ひらく (こころをひらく), "to open your heart", means to open up to someone and trust them.

少すこしずつ心こころを開ひらいてくれた。 — Little by little, they opened up to me. (casual)

What does 開催かいさい mean?

開催かいさい (かいさい) is a formal word for holding an event: イベントを開催かいさいする.

来月らいげつ、展示会てんじかいが開催かいさいされます。 — An exhibition will be held next month. (polite, formal)

How do you open a file or app?

On a computer, use 開ひらく (ひらく): ファイルを開ひらく, "open a file". アプリを起動きどうする (きどうする) is "launch an app".

このファイルが開ひらかない。 — This file won't open. (casual, read ひらかない)

You may also hear このファイルが開あけない, read ひらけない, which means "I can't get this file open". For verb types, see Japanese verb groups.

Common mistakes

  • Saying 窓まどが開あけた for "the window opened". It is 窓まどが開あいた. 開あける takes the thing being opened with を.
  • Reading every 開ひらく as あく. For books, umbrellas, hands and meetings it is ひらく.
  • Using オープン as the basic "it's open now". To ask whether a shop is open now, 開ひらいていますか? or 営業中えいぎょうちゅうですか? is a useful choice.
  • Mixing 開あける and 空あける. 席せきを空あける is "leave a seat empty", not "open a seat".
  • Mixing 閉しめる, 閉しまる and 閉とじる. Doors and windows are 閉しめる / 閉しまる. Books and files are 閉とじる.

Practice

Try each answer before opening it. These reuse words from above in new situations, so you need the pattern, not the memorized sentence.

1. Ask politely, "Please open the box."

Show answer

箱はこを開あけてください。 — 開あける with を.

2. Say "The automatic door opened."

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自動じどうドアが開あいた。 — 開あく (あく) with が.

3. Say casually, "The curtains are open."

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カーテンが開ひらいているよ。 — 開ひらいている (あいている), the state. ひらいている is also possible.

4. A teacher says, "Please open your clenched hand." What do they say?

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握にぎった手てを開ひらいてください。 — 手てを開ひらく (ひらく): the hand opens out.

5. A dentist says, "Please open your mouth." What do they say?

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口くちを開あけてください。 — 口くちをあける, a gap appears, so 開あける.

6. Say "The rose bud opened."

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バラのつぼみが開ひらいた。 — 開ひらく (ひらく) with が. For a plain bloom report you could say バラが咲さいた.

7. Which signs on a ramen shop door mean "we are open"?

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営業中えいぎょうちゅう and 商あきない中なか — 準備中じゅんびちゅう and 仕度したく中なか mean "not open yet".

8. Ask a friend to keep Friday free for you, using おく.

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金曜日きんようびを空あけておいてね。 — 空あける (make free), not 開あける.

9. Say "I can't open the lid of this jar" (your hand is not strong enough).

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このびんのふたが開あけられない。 — The potential form of 開あける: you are unable to open it. このびんのふたを開あけられない is also correct.

10. You are shut in a room in an anime. Shout "The door won't open!"

Show answer

ドアが開ひらかない! — 開あく (あく) in the negative: it states that the door does not open.

FAQ

Can I use ひらく for doors? Yes. ドアをひらく exists and is a normal use of ひらく. For an everyday request, ドアを開あけて is the basic way to say it.

How do I say "open up!" politely? 開あけてください. For a very polite request, 開あけていただけますか? Casual 開あけて is fine with friends.

What is the difference between 店みせを開ひらく and 店みせが開ひらく? 店みせを開ひらく (みせをひらく) means to open a business, as in 自分じぶんの店みせを開ひらく. 店みせが開ひらく (みせがあく) means the shop starts the day's business. Do not rely on the particle alone, because 店みせがひらく is also possible.

Which あける kanji do I write for a seat or a schedule? 空あける: 席せきを空あける, 予定よていを空あける.

What do I say to close a book? 本ほんを閉とじる (ほんをとじる). 閉しめる is for doors and windows.

Vocabulary from this article

Tap the block to select all of it, then copy. In Anki: File → Import, note type Basic, separator Tab — the first column becomes the front, the second the back.

窓を開ける	まどをあける — to open a window
ドアが開く	ドアがあく — the door opens
本を開く	ほんをひらく — to open a book
会議を開く	かいぎをひらく — to hold a meeting
カーテンを閉める	カーテンをしめる — to close the curtains
ドアが閉まる	ドアがしまる — the door closes
本を閉じる	ほんをとじる — to close a book
営業中	えいぎょうちゅう — open for business
準備中	じゅんびちゅう — preparing, closed
商い中	あきないちゅう — open (old-style sign)
仕度中	したくちゅう — getting ready, not open yet
席を空ける	せきをあける — to leave a seat empty
心を開く	こころをひらく — to open up
開催	かいさい — holding (an event)

I'm Yuuki, a Japanese teacher based in Tokyo. I've taught on italki as a Top 1% teacher and watched over 1,500 anime, so most of the example sentences on this blog come from lines I've actually heard students ask about — including this one, which comes up in nearly every beginner's first few lessons. For practice with feedback, Book a trial lesson · $13, or work through Japanese practice exercises first.

Sources: the author's own lessons and standard reference dictionaries.

More drills like the ones above, plus a timed JLPT-style mock test: Practice · N5 · Read something at this level: JLPT N5 stories with audio

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