費やす · godan verb (-su)
| Form | Positive | Negative |
|---|---|---|
| Dictionary | 費やす | 費やさない |
| Polite | 費やします | 費やしません |
| Past polite | 費やしました | 費やしませんでした |
| Past | 費やした | 費やさなかった |
| Te-form | 費やして | 費やさないで |
| Desire | 費やしたい | 費やしたくない |
| Potential | 費やせる | 費やせない |
| Passive | 費やされる | 費やされない |
| Causative | 費やさせる | 費やさせない |
| Causative passive | 費やさせられる | 費やさせられない |
| Volitional | 費やそう | |
| Polite volitional | 費やしましょう | |
| Imperative | 費やせ | 費やすな |
| Conditional | 費やせば | 費やさなければ |
| Tara conditional | 費やしたら | 費やさなかったら |
godan verb (-su), transitive verb
Neutral use for spending money, time, effort, or resources. Often implies intentional allocation.
He spent a lot of time on his research.
We ended up spending most of the budget on this project.
godan verb (-su), transitive verb
Negative nuance: spending carelessly or on something worthless. Often used with 無駄に.
He squandered his entire fortune on gambling.
It's a waste to spend time on such things.
godan verb (-su), transitive verb
Positive nuance: giving time, effort, or life to a worthy cause or purpose. Often used with ～に一生を費やす.
She devoted her life to education.
He devoted all his energy to solving this problem.
He spent a lot of time on his research.
We ended up wasting precious resources.
He devoted his entire life to that research.
We spent three years on this project.
費やす means to spend or use up time, money, or effort, while 注ぎ込む focuses on the image of directing that resource intensively into a target.