Japanese i-adjective
hayai — fast 速い
Explore the principal positive, negative, past, non-past and conditional forms of this Japanese adjective.
How i-adjectives conjugate
The final い changes to create negative, past and connecting forms. The adjective itself carries this grammatical information, so a separate verb is not required in the plain forms.
Conjugation table
The English glosses are approximate; the natural translation depends on the surrounding sentence.
| Form | Style | Positive | Negative |
|---|---|---|---|
| Present (non-past) | Plain | is fast hayai 速い | is not fast hayakunai 速くない |
| Polite | hayai desu 速いです | hayakunai desu 速くないです | |
| Past | Plain | was fast hayakatta 速かった | was not fast hayakunakatta 速くなかった |
| Polite | hayakatta desu 速かったです | hayakunakatta desu 速くなかったです | |
| Presumptive | Plain | will probably be fast hayai darō 速いだろう | hayakunai darō 速くないだろう |
| Polite | hayai deshō 速いでしょう | hayakunai deshō 速くないでしょう | |
| Conditional | Standard | if it is fast hayakereba 速ければ | if it is not fast hayakunakereba 速くなければ |
| Connecting form | Standard | hayakute 速くて | hayakunakute 速くなくて |
These conjugations are generated automatically and are intended as a learning guide. Check the natural usage in context when accuracy is important.