# べし
## Japanese
### Etymology

* Alternative spelling
* 可し (obsolete)
From Old Japanese. First attested in the Kojiki of 712 CE.

### Pronunciation

* IPA: [be̞ɕi]

### Suffix

べし • (-beshi)
* (attaching to terminal form) must, shall
    Antonym: まじ (maji)
** indicating certainty
    地(ち)方(ほう)路(ろ)線(せん)のいくつかはやがて廃(はい)止(し)されるべき運(うん)命(めい)にある。
       Chihō rosen no ikutsuka wa yagate haishisarerubeki unmei ni aru.
       Some of the local railways will soon be abolished.
** indicating requirement
    この件(けん)については君(きみ)が責(せき)任(にん)をとるべきだ。
       Kono ken ni tsuite wa kimi ga sekinin o torubeki da.
       You should take responsibility on this.
    明日(あした)は八(はち)時(じ)までに出(しゅっ)勤(きん)すべし。
       Ashita wa hachiji made ni shukkin-subeshi.
       You should work until eight o'clock tomorrow.
    英(えい)語(ご)は声(こえ)を出(だ)して読(よ)むべきだ。
       Eigo wa koe o dashite yomu beki da.
       You should read English aloud.
    来(らい)年(ねん)の博(はく)覧(らん)会(かい)開(かい)催(さい)に間(ま)に合(あ)わせるべく、突(とっ)貫(かん)工(こう)事(じ)が行(おこな)われている。
       Rainen no hakurankai kaisai ni ma ni awaseru beku, tokkan kōji ga okonawareteiru.
       In order to hold the exhibition in time next year, hasty construction is underway.

#### Usage notes

* This word is morphologically a clitic. It is classified as 助動詞 (jodōshi, “auxiliary verb”) in traditional Japanese grammar. Syntactically, it is essentially a verb suffix, attaching only to the terminal or predicative form of the verb rather than to any of the other conjugation stems.
* This inflects very similarly to Classical adjectives.
* The verb する (suru, “to do”) typically takes the classical terminal form す (su), rather than the modern terminal form する (suru), when used with べし (beshi): すべし (subeshi) ("should do").
** However, there is a minority that uses するべし (surubeshi).
* It is common to see the adnominal form べき (beki) + auxiliary だ (da) in terminal position instead of the expected terminal form べし (beshi).

#### Inflection

Stem forms :
| Imperfective (未然形) | べから | bekara |
| Continuative (連用形) | べく | beku |
| Terminal (終止形) | べし | beshi |
| Attributive (連体形) | べき べかる | beki bekaru |
| Hypothetical (仮定形) | べけれ | bekere |
| Imperative (命令形) | — | — |
| Key constructions ||||
| Informal negative | べきじゃない | beki ja nai |
| Informal past | べきだった | beki datta |
| Informal negative past | べきじゃなかった | beki ja nakatta |
| Formal | べきです | beki desu |
| Formal negative | べきではありません | beki de wa arimasen |
| Formal past | べきでした | beki deshita |
| Formal negative past | べきではありませんでした | beki de wa arimasen deshita |
| Conjunctive | べく べくて | beku bekute |
| Conditional | べきだったら | beki dattara |
| Provisional | べければ | bekereba |
| Volitional | べきだろう べきでしょう | beki darō beki deshō |
| Adverbial | べく | beku |
| Degree | — | — |
Stem forms :
| Irrealis (未然形) | べく$^{[1]}$ べから$^{[2]}$ | べく$^{[1]}$ べから$^{[2]}$ | beku bekara |
| Continuative (連用形) | べく$^{[1]}$ べかり$^{[2]}$ | べく$^{[1]}$ べかり$^{[2]}$ | beku bekari |
| Terminal (終止形) | べし | べし | besi |
| Attributive (連体形) | べき べかる | べき べかる | beki bekaru |
| Realis (已然形) | べけれ | べけれ | bekere |
| Imperative (命令形) | べかれ | べかれ | bekare |
| Key constructions ||||
| Negative | べからず | べからず | bekarazu |
| Contrasting conjunction | べけれど | べけれど | bekeredo |
| Causal conjunction | べければ | べければ | bekereba |
| Conditional conjunction | べくば | べくば | bekuba |
| Past tense (firsthand knowledge) | べかりき | べかりき | bekariki |
| Past tense (secondhand knowledge) | べかりけり | べかりけり | bekarikeri |
| Adverbial | べく | べく | beku |
| $^{[1]}$Without auxiliary verb. $^{[2]}$With auxiliary verb. ||||
* The modern conjugation of べし is a combination of its classical conjugation and the conjugation of べき + だ (da).

### References

* ↑ “可”, in 日本国語大辞典 [Nihon Kokugo Daijiten]‎ (in Japanese), concise edition, Tokyo: Shogakukan, 2006
* ↑ https://www.nhk.or.jp/bunken/research/kotoba/20210401_3.html