Meaning & Usage
✨ Basic Meaning
‘Must’, ‘Have to’, or ‘Obliged to’.
🎯 Primary Function
To express obligation or a situation where something is necessary or required.
📋 Grammar Structure
Verb (Nai-form, remove い) + ければいけない
Stem (remove い) + くなければいけない
Stem + でなければいけない / じゃなければいけない
N/A (This form is already a double negative)
🎭 Usage Contexts
Formal Situations
Used as ‘なければなりません’ (nakereba narimasen) in polite or business settings.
Informal Situations
Shortened to ‘なきゃ’ (nakya) or ‘なくちゃ’ (nakucha) in casual conversation.
Written Language
Found in instructions, manuals, and formal rulebooks.
Spoken Language
Commonly used to discuss daily chores and immediate needs.
💡 Common Applications
Expressing Personal Duty
Used when the speaker feels a personal necessity to do something.
Example: ダイエット中だから、走らなければいけない。(I’m on a diet, so I have to run.)
Social Rules and Manners
Used to describe expected social behaviors or rules in a specific location.
Example: 靴を脱がなければいけません。(You must take off your shoes.)
Logical Necessity
Used to state conditions that must be met for a certain outcome.
Example: 安くなければいけない。(It must be cheap – otherwise I won’t buy it.)
Frequency
High
Difficulty
JLPT N4
Tag:
Example Sentences
Example #1
もうすぐ帰らなければいけない。
Furigana: もうすぐかえらなければいけない。
Romaji: Mōsugu kaeranakereba ikenai.
English: I have to go home soon.
Example #2
試験のために、一生懸命勉強しなければいけない。
Furigana: しけんのために、いっしょうけんめいべんきょうしなければいけない。
Romaji: Shiken no tame ni, isshōkenmei benkyō shinakereba ikenai.
English: You must study hard for the exam.
Example #3
毎朝、薬を飲まなければいけません。
Furigana: まいあさ、くすりをのまなければいけません。
Romaji: Maiasa, kusuri o nomanakereba ikemasen.
English: I have to take medicine every morning.
Example #4
約束を守らなければいけません。
Furigana: やくそくをまもらなければいけません。
Romaji: Yakusoku o mamoranakereba ikemasen.
English: We must keep our promises.
Example #5
野菜は新鮮でなければいけません。
Furigana: やさいはしんせんでなければいけません。
Romaji: Yasai wa shinsen de nakereba ikemasen.
English: The vegetables must be fresh.
Example #6
明日の朝は6時に起きなければいけない。
Furigana: あしたのあさはろくじにおきなければいけない。
Romaji: Ashita no asa wa rokuji ni okinakereba ikenai.
English: I must wake up at 6 o’clock tomorrow morning.
Example #7
この質問の答えは正しくなければいけない。
Furigana: このしつもんのこたえはただしくなければいけない。
Romaji: Kono shitsumon no kotae wa tadashiku nakereba ikenai.
English: The answer to this question must be correct.
Example #8
パスポートを忘れなければいけない。
Furigana: パスポートをわすれてはいけない（わすれなければいけない）。
Romaji: Pasupōto o wasurenakereba ikenai.
English: You must not forget your passport. (I must not forget…)
Example #9
今日中に宿題を終わらせなければいけない。
Furigana: きょうじゅうにしゅくだいをおわらせなければいけない。
Romaji: Kyōjū ni shukudai o owarasenakereba ikenai.
English: I have to finish my homework by today.
Example #10
図書館では静かにしなければいけません。
Furigana: としょかんではしずかにしなければいけません。
Romaji: Toshokan de wa shizuka ni shinakereba ikemasen.
English: Everyone must be quiet in the library.
Notes & Nuances
📌 Important Points
Double Negative Logic
‘Ikenai’ literally means ‘cannot go’ or ‘is not good/permitted’, making the double negative a positive obligation.
Example: 明日は早く起きなければいけない。(I have to wake up early tomorrow.)
Subjectivity vs. Objectivity
‘Ikenai’ is often more subjective (speaker’s feelings), whereas ‘Naranai’ is more objective (social/legal rules).
Example: 仕事に行かなければならない。(I must go to work – social duty.) vs 仕事に行かなければいけない。(I have to go to work – personal necessity.)
⚠️ Common Mistakes
❌ 行かないければいけない (Ikanai-kereba ikenai)
✅ 行かなければいけない (Ikana-kereba ikenai)
Learners often forget to drop the ‘i’ from the ‘nai’ form before adding ‘kereba’.
❌ 寝らなければいけない (Neranakereba ikenai)
✅ 寝なければいけない (Nenakereba ikenai)
Mixing up the ‘nai-form’ of Ru-verbs (Group 2) and U-verbs (Group 1).
🏛️ Cultural Context
Politeness Level: Medium (plain form). Use ‘〜なければいけません’ for polite speech.
Social Situations: Expressing duty in Japan often sounds softer than the English ‘must’, depending on the tone.
Regional Variations: In Kansai, ‘なあかん’ (naakan) is frequently used instead.
🔍 Subtle Differences
なければいけない vs なければならない
‘Ikenai’ is used for personal/conversational necessity, while ‘Naranai’ is for objective/formal duty.
When to use: Use ‘Ikenai’ for daily chores or personal rules; use ‘Naranai’ for laws or formal speeches.
📝 Conjugation Notes
The structure literally means ‘if you don’t do [verb], it is no good’. It uses the conditional ‘ba’ form of the negative ‘nai’.
🔊 Pronunciation Tips
The ‘kereba’ part is often spoken quickly. In casual speech, it often slurs into ‘nakya’.
🧠 Memory Tips
Think of it as: ‘Nai’ (Not) + ‘Kereba’ (If) + ‘Ikenai’ (No good). If I don’t do it, it’s no good!
Other Grammar
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