GrammarJLPT N5
→ should
Should / Ought to (Moral Obligation or Strong Recommendation)
JLPT N5Auxiliary verbFormal
べき expresses a strong sense of moral obligation, duty, or strong recommendation, roughly equivalent to English "should" or "ought to." It carries a more formal, principled tone than the softer suggestion ほうがいい ("it would be better to") and differs from なければならない ("must / have to"), which focuses on external necessity or rules rather than moral judgment. べき is often used when the speaker believes something is the right or proper thing to do based on common sense, social norms, or ethical standards. It attaches to the dictionary form of verbs (with the notable exception of する, which can become either <strong>すべき</strong> or <strong>するべき</strong>). In the negative, the construction べきではない ("should not") is far more common than the rare べからず. Because of its firm, sometimes preachy tone, べき is more frequent in writing, speeches, and formal discussions than in casual everyday conversation.
Functions
#1 Strong recommendation or moral obligation
Structure
Verb (dictionary form) + べきだ
学生は毎日勉強するべきだ。
Here べき attaches to the dictionary form する to express a strong moral or normative recommendation. The speaker is not merely suggesting it would be nice to study; rather, they are stating that studying daily is the proper, expected thing for students to do. This tone makes べきだ sound authoritative and principled, suitable for advice columns, essays, or serious conversations.Students should study every day.
Structures
- Verb (dictionary form)
- Verb (dictionary form) + べき (+ だ / です)
- する (special case)
- するべき / すべき (+ だ / です)
- Negative (should not)
- Verb (dictionary form) + べきではない
- Before a noun
- Verb (dictionary form) + べき + Noun
Common mistakes
A very common error is conjugating the verb before attaching べき, such as saying 食べますべき or 行ったべき. Remember that べき always attaches to the dictionary (plain) form of the verb, never the masu-stem or past tense. Another frequent mistake is confusing べき with ほうがいい; while both translate as "should," べき implies moral duty or strong principle, whereas ほうがいい is a softer, more personal suggestion. Learners also sometimes try to negate by saying べきじゃない in writing, which is grammatically possible but overly casual; the standard form is べきではない. Finally, some learners overuse べき in casual conversation, which can sound preachy or stiff; in everyday speech, ほうがいい or たほうがいい is often more appropriate.
Related
はずほうがいいなければならないべきではないものだつもり