Meaning
べき indicates that something is natural, necessary, or obligatory to do. It expresses what should happen or what one ought to do. When used at the end of a sentence, it takes the form べきだ. The negative form べきではない means 'should not' or 'must not.' Note that する + べき can become either するべき or すべき, with no difference in meaning.
Formation
| Part of speech | Formation |
|---|---|
| 动词辞书形 | べき（だ） |
Examples
-
ものが盗まれたら、警察に連絡すべきだ。
If something is stolen, you should contact the police. -
この建物の中では、タバコを吸うべきではありません。
You should not smoke inside this building. -
山下さんのせいで、今回のプロジェクトの完成は締め切りに間に合わなかった。彼は責任を取るべきだ。
It's Yamashita's fault that the project wasn't completed on time. He should take responsibility.
Summary
- Use べき/べきだ to express duty, obligation, or what naturally should be done
- Negative form べきではない means 'should not' or 'must not do something'
- Past form べきだった expresses regret about not doing something that should have been done