| Form | Conjugation | 
|---|---|
| Plain? | 研く | 
| Past? | 研いた | 
| Negative? | 研かない | 
| Volitional? | 研こう | 
| Imperative? | 研け | 
| Polite imperative? | 研きなさい | 
| 〜たい? | 研きたい | 
| Conditional (〜えば)? | 研けば | 
| Conditional (〜たら)? | 研いたら | 
| Potential? | 研ける | 
| Passive? | 研かれる | 
| Causative? | 研かせる | 
| Prohibitive? | 研くな | 
| 〜ます? | 研きます |