modality N3 common casualpolitewritten
〜べきだ — should ~ / ought to ~
〜べきだ ・ べきだ
Meaning
- should ~ / ought to ~ — what is right or advisable to do, as a matter of principle
Key sentence
約束は守るべきだ。
You should keep your promises.
Formation
| Attaches to | Form | Example |
|---|---|---|
| verb (dictionary form) | V(dict) + べきだ | 守るべきだ / 助けるべきだ |
| する | する → するべき／すべき (both accepted) | 注意すべきだ |
Variants
すべき / するべき — With する, both すべき and するべき are correct; すべき is a touch more formal/written.
Examples
困っている人がいたら、助けるべきだ。
If someone's in trouble, you ought to help them.
もっと早く医者に行くべきだった。
I should have gone to the doctor sooner.
学生は今しかできないことに挑戦すべきだ。
Students should take on things they can only do now.
When you can't use it
- べき carries a moral or social 'this is the right thing' tone, so it can sound preachy aimed at a listener; soften real advice with 〜べきだと思う. Past 〜べきだった = 'should have ~ (but didn't).'
Easily confused with
〜ほうがいい 〜ほうがいい = advice for this particular situation ('you'd be better off ~ing'); べきだ = a general principle of what's right. べき is stronger and more absolute. 〜はずだ The classic pair. べきだ = obligation ('ought to do it'); はずだ = expectation ('should be the case'). 来るべきだ = he ought to come; 来るはずだ = I expect him to come. 〜なければならない なければならない = a hard necessity, often externally imposed ('must'); べきだ = moral/social propriety ('the right thing to do').
See 〜べきだ in real sentences
Jengo shows 〜べきだ the way you actually meet it: inside real Japanese sentences, so it sticks instead of staying an abstract rule.
Study it in JengoSources Compiled with reference to A Dictionary of Intermediate Japanese Grammar.