必要 (hitsuyou) conjugation
necessary
必要 (ひつよう, hitsuyou) is a na-adjective. Na-adjectives behave like nouns. The word itself never changes — you conjugate だ/です after it, and you need な to put it in front of a noun.
Conjugation table
| Form | Plain (casual) | Polite (~です) | When you use it |
|---|---|---|---|
| Dictionary / plain | 必要だ hitsuyouda | 必要です hitsuyoudesu | The form you look up. Also the casual “is ~”. |
| Negative | 必要じゃない hitsuyoujanai | 必要じゃないです hitsuyoujanaidesu | “is not ~”. |
| Past | 必要だった hitsuyoudatta | 必要でした hitsuyoudeshita | “was ~”. |
| Past negative | 必要じゃなかった hitsuyoujanakatta | 必要じゃなかったです hitsuyoujanakattadesu | “was not ~”. |
| Te-form | 必要で hitsuyoude | — | Links to the next clause: “~ and …”. |
| Adverb | 必要に hitsuyouni | — | Turns it into “~ly”, describing a verb. |
| Before a noun | 必要な〜 hitsuyouna〜 | — | How it attaches when it modifies a noun. |
| Conditional (~ば/なら) | 必要なら hitsuyounara | — | “if it is ~”. |
| Conditional (~たら) | 必要だったら hitsuyoudattara | — | “if / when it is ~”. The everyday conditional. |
| Become (~なる) | 必要になる hitsuyouninaru | 必要になります hitsuyouninarimasu | “becomes ~” — the change-of-state form. |
| Too much (~すぎる) | 必要すぎる hitsuyousugiru | 必要すぎます hitsuyousugimasu | “too ~”. |
| Looks ~ (~そう) | 必要そう hitsuyousou | 必要そうです hitsuyousoudesu | “looks / seems ~” from appearance. |
🔊 Tap any Japanese word to hear it spoken.
Why it conjugates this way
Na-adjectives behave like nouns. The word itself never changes — you conjugate だ/です after it, and you need な to put it in front of a noun.
See the full rules in the adjective conjugation guide.