Meaning & Usage
✨ Basic Meaning
Should, ought to, it is proper/right to do.
🎯 Primary Function
To express a sense of strong obligation, duty, appropriateness, or logical expectation.
📋 Grammar Structure
Verb (dictionary form) + べきだ (する becomes すべきだ or するべきだ)
N/A (The pattern primarily attaches to verbs. To express the necessity of a state, use a verb form like 〜であるべきだ.)
N/A (Use Noun/な-adj Stem + である + べきだ for very formal or conceptual expression.)
Verb (dictionary form) + べきではない / べきじゃない
🎭 Usage Contexts
Formal Situations
Frequently used in official statements, policy discussions, and strong arguments.
Informal Situations
Used to give firm personal advice or express disappointment/judgment to close friends or family.
Written Language
Very common in essays, editorials, academic papers, and articles demanding a specific course of action.
Spoken Language
Common when the speaker wishes to emphasize the correctness or necessity of an action. The contracted form べきじゃない is common.
💡 Common Applications
Expressing Moral/Social Obligation
Used to state what is generally accepted as the correct or moral action in a society.
Example: 困っている人がいたら助けるべきだ。 (If there is someone in trouble, you should help them.)
Giving Strong Advice or Recommendation
Used to give firm advice based on the speaker’s judgment of what is best or necessary.
Example: 健康のためにもっと早く寝るべきだ。 (For the sake of your health, you ought to go to bed earlier.)
Expressing Regret/Criticism (Past Tense)
The form べきだった expresses regret over an action that was not taken or criticism of someone else’s past mistake.
Example: もっと早く始めるべきだった。 (I should have started earlier.)
Frequency
High, especially in formal writing, speeches, and strong advice/criticism.
Difficulty
N3 (Intermediate)
Tag:
Example Sentences
Example #1
約束は守るべきだ。
Furigana: やくそくはまもるべきだ。
Romaji: Yakusoku wa mamoru beki da.
English: One should keep promises.
Example #2
親に感謝すべきだと私は思う。
Furigana: おやにかんしゃすべきだとわたしはおもう。
Romaji: Oya ni kansha suru beki da to watashi wa omou.
English: I think we ought to be grateful to our parents.
Example #3
すぐに謝るべきだったのに、彼はしなかった。
Furigana: すぐにやまわるべきだったのに、かれはしなかった。
Romaji: Sugu ni ayamaru beki datta noni, kare wa shinakatta.
English: He should have apologized immediately, but he didn’t.
Example #4
学生はもっと勉強に集中すべきだ。
Furigana: がくせいはもっとべんきょうにしゅうちゅうすべきだ。
Romaji: Gakusei wa motto benkyou ni shuuchuu suru beki da.
English: Students ought to concentrate more on their studies.
Example #5
そんな無責任な行動は取るべきではない。
Furigana: そんなむせきにんなこうどうはとるべきではない。
Romaji: Sonna musekinin na koudou wa toru beki dewa nai.
English: You shouldn’t take such irresponsible actions.
Example #6
これは後世に残すべき貴重な文化だ。
Furigana: これはこうせい に のこすべき きちょうなぶんかだ。
Romaji: Kore wa kōsei ni nokosu beki kichō na bunka da.
English: This is a valuable culture that should be preserved for future generations.
Example #7
ルールは破るべきものではない。
Furigana: ルールはやぶるべきものではない。
Romaji: Rūru wa yaburu beki mono dewa nai.
English: Rules are not things that should be broken.
Example #8
彼女はもうすぐ着くはずだから、そろそろ連絡すべきだ。
Furigana: かのじょはもうすぐつくはずだから、そろそろれんらくすべきだ。
Romaji: Kanojo wa mō sugu tsuku hazu dakara, sorosoro renraku suru beki da.
English: Since she should arrive soon, I should contact her now.
Example #9
疲れているなら、少し休むべきだよ。
Furigana: つかれているなら、すこしやすむべきだよ。
Romaji: Tsukarete iru nara, sukoshi yasumu beki da yo.
English: If you’re tired, you should rest a little.
Example #10
まず何から始めるべきか、計画を立てよう。
Furigana: まずなにからはじめるべきか、けいかくをたてよう。
Romaji: Mazu nani kara hajimeru beki ka, keikaku o tateyō.
English: Let’s make a plan about what we should start with first.
Notes & Nuances
📌 Important Points
Modifying Nouns
べき can be used to modify nouns, acting as a な-adjective (V-ru + べき + Noun).
Example: これは検討すべき問題だ。
Past Negative Expression (Shouldn’t have done)
The past negative べきではなかった expresses regret or disappointment that a certain action was not avoided.
Example: こんな簡単な間違いをするべきではなかった。
The form of する (to do)
The verb する has a special form, すべきだ, although するべきだ is also widely accepted and used in modern Japanese.
Example: すべきことはやった。 (I did what needed to be done.)
⚠️ Common Mistakes
❌ 旅行に行くべきだった。 (Correct) → 旅行に行ったべきだ。 (Incorrect)
✅ V (dictionary form) + べきだ
The pattern attaches to the dictionary form of the verb, not the past tense (V-ta form).
❌ すぐしべきだ。 (Incorrect)
✅ する → すべきだ or するべきだ
While するべきだ is very common, the classical and more emphatic form is すべきだ. Avoid using しべきだ.
🏛️ Cultural Context
Politeness Level: Relatively neutral to slightly formal. It carries weight and is often used when emphasizing social responsibility. It can sound critical if directed at the listener.
Social Situations: Used in situations requiring serious reflection on duty, social norms, or moral conduct. Can be perceived as scolding or lecturing if not used carefully.
Regional Variations: Standard Japanese. No significant regional variations in usage.
🔍 Subtle Differences
べきだ vs. 〜ほうがいい
ほうがいい is soft advice (better to), while べきだ is strong advice or moral obligation (ought to/should).
When to use: Use ほうがいい for suggestions (e.g., You might feel better if you do this). Use べきだ for duties or serious advice (e.g., You are required by morality/logic to do this).
べきだ vs. 〜なければならない
なければならない expresses necessity enforced by external rules or absolute need (Must/Have to). べきだ expresses necessity based on moral, social, or logical propriety (Ought to/Should).
When to use: Use なければならない for rules/laws (e.g., You must pay taxes). Use べきだ for what is right (e.g., You should respect the elderly).
べきだ vs. 〜はずだ
はずだ expresses expectation or probability (it is supposed to). べきだ expresses duty or propriety (it is proper to).
When to use: はずだ relates to certainty (The bus should arrive now). べきだ relates to obligation (The bus driver should be polite).
📝 Conjugation Notes
べきだ functions grammatically like a な-adjective. When modifying a noun, it takes the form べき: 「守るべきルール (Rules that should be followed).」 The past tense is べきだった.
🔊 Pronunciation Tips
The sound for べき (beki) should be clear and often carries a slightly emphatic tone to reflect the weight of the statement.
🧠 Memory Tips
Relate べきだ to the English ‘Ought to.’ Think of it as ‘what is proper or duty’ (べき). This makes it stronger than simple advice.
Other Grammar
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