Meaning & Usage
✨ Basic Meaning
Unintentionally, accidentally, or doing something against one’s better judgment.
🎯 Primary Function
To express that an action occurred without the speaker’s deliberate intention or despite their attempt to stop it.
📋 Grammar Structure
つい + Verb (often in 〜てしまう form)
Not applicable (usually modifies verbs).
Not applicable (usually modifies verbs).
Usually not used in negative form; used to describe actions that *did* happen unintentionally.
🎭 Usage Contexts
Formal Situations
Used in apologies, though ‘ukkari’ or ‘fuchuui’ might be used for official business errors.
Informal Situations
Extremely common in daily conversation to explain mistakes or habits.
Written Language
Common in personal blogs, diaries, and narrative fiction.
Spoken Language
Very common; often followed by the ‘~te shimatta’ ending.
💡 Common Applications
Regretful actions
Used when you regret an action that you knew you shouldn’t have done.
Example: つい飲みすぎてしまった。 (I unintentionally drank too much.)
Instinctive habits
Used for habits or repetitive actions done without conscious thought.
Example: 暇になると、ついスマホを見てしまう。 (When I’m free, I unintentionally check my phone.)
Emotional slips
Used when an emotion triggers an action you couldn’t suppress.
Example: 悲しくて、つい泣いてしまった。 (I was so sad I couldn’t help but cry.)
Frequency
High
Difficulty
N3
Tag:
Example Sentences
Example #1
ダイエット中なのに、ついまた甘いものを食べてしまった。
Furigana: ダイエットちゅうなのに、ついまたあまいものをたべてしまった。
Romaji: Daietto chuu na no ni, tsui mata amai mono o tabete shimatta.
English: I unintentionally ate sweets again, even though I’m on a diet.
Example #2
面白かったので、つい夜更かしをして本を読んでしまった。
Furigana: おもしろかったので、ついよふかしをしてほんをよんでしまった。
Romaji: Omoshirokatta node, tsui yofukashi o shite hon o yonde shimatta.
English: It was so interesting that I accidentally stayed up late reading the book.
Example #3
秘密だったのに、つい彼に話してしまった。
Furigana: ひみつだったのに、ついかれにはなしてしまった。
Romaji: Himitsu datta no ni, tsui kare ni hanashite shimatta.
English: It was a secret, but I accidentally told him.
Example #4
とても疲れていたので、電車の中でつい居眠りをしてしまった。
Furigana: とてもつかれていたので、でんしゃのなかでついいねむりをしてしまった。
Romaji: Totemo tsukarete ita node, densha no naka de tsui inemuri o shite shimatta.
English: I was so tired that I unintentionally dozed off on the train.
Example #5
セールだったので、つい必要のない物まで買ってしまった。
Furigana: セールだったので、ついひつようのないものまでかってしまった。
Romaji: Seeru datta node, tsui hitsuyou no nai mono made katte shimatta.
English: The sale was so good that I accidentally bought things I didn’t need.
Example #6
彼の冗談が面白くて、つい吹き出してしまった。
Furigana: かれのじょうだんがおもしろくて、ついふきだしてしまった。
Romaji: Kare no joudan ga omoshirokute, tsui fukidashite shimatta.
English: His joke was so funny that I couldn’t help but laugh out loud.
Example #7
緊張すると、つい髪を触ってしまう。
Furigana: きんちょうすると、ついかみをさわってしまう。
Romaji: Kinchou suru to, tsui kami o sawatte shimau.
English: When I’m nervous, I unintentionally start playing with my hair.
Example #8
急いでいたので、つい傘を忘れてきてしまった。
Furigana: いそいでいたので、ついかさをわすれてきてしまった。
Romaji: Isoide ita node, tsui kasa o wasurete kite shimatta.
English: I was in a hurry and accidentally left my umbrella behind.
Example #9
節約するつもりだったのに、つい贅沢なランチを注文した。
Furigana: せつやくするつもりだったのに、ついぜいたくなランチをちゅうもんした。
Romaji: Setsuyaku suru tsumori datta no ni, tsui zeitaku na ranchi o chuumon shita.
English: I was supposed to save money, but I accidentally ordered a luxurious lunch.
Example #10
懐かしい写真を見ると、つい眺めてしまう。
Furigana: なつかしいしゃしんをみると、ついながめてしまう。
Romaji: Natsukashii shashin o miru to, tsui nagamete shimau.
English: When I see a nostalgic photo, I unintentionally stare at it for a long time.
Notes & Nuances
📌 Important Points
Emphasis on Lack of Control
The word implies a psychological lapse where your self-control failed momentarily.
Example: つい、言ってしまった。 (I accidentally said it.)
Pairing with ~te shimau
‘Tsui’ usually involves a lapse in judgment over a short period, while ‘Omowazu’ is an instantaneous physical reflex.
Example: 思わず叫んだ (I screamed reflexively) vs つい夜更かしした (I accidentally stayed up late).
⚠️ Common Mistakes
❌ つい、わざと買った。
✅ つい買ってしまった。
‘Tsui’ indicates an unintentional action. ‘Wazato’ (on purpose) is the direct opposite.
❌ つい食べた。(Less natural without context)
✅ つい食べてしまった。
While ‘tsui tabeta’ is grammatically okay in casual speech, the combination with ‘~te shimatta’ is much more natural to express regret.
🏛️ Cultural Context
Politeness Level: Neutral to casual. Used by all ages.
Social Situations: Commonly used when making excuses or confessing minor weaknesses (like eating too much or oversleeping).
Regional Variations: Standard Japanese. In some dialects, variations exist, but ‘tsui’ is understood everywhere.
🔍 Subtle Differences
つい vs. 思わず (Omowazu)
‘Omowazu’ is a reflex (like jumping when surprised). ‘Tsui’ is often a failure of willpower or a habit.
When to use: Use ‘Omowazu’ for immediate physical reactions; use ‘Tsui’ for habits or lapses in judgment.
つい vs. うっかり (Ukkari)
‘Ukkari’ focuses on carelessness or forgetting. ‘Tsui’ focuses on doing something you shouldn’t have done.
When to use: Use ‘Ukkari’ for forgetting keys; use ‘Tsui’ for eating a second piece of cake.
📝 Conjugation Notes
‘Tsui’ is an adverb and does not conjugate. It is almost always paired with the ‘te-form + shimau’ to emphasize completion and regret.
🔊 Pronunciation Tips
The ‘u’ sound is short. It is pronounced quickly to emphasize the ‘unintentional’ nature.
🧠 Memory Tips
Think of ‘tsui’ as the sound of ‘slipping’ into an action. You were walking on the path of your diet, but you ‘tsui’ (slipped) into a donut shop.
Other Grammar
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