modality N2 common politewritten
〜かねる — cannot ~ / be unable to ~ (polite decline)
〜かねる ・ かねる
Builds on 連用形（ます形）
Meaning
- cannot ~ / be unable to ~ — a formal, polite way to say something can't be done, often softening a refusal
Key sentence
その件につきましては、お答えしかねます。
I'm afraid I am unable to answer regarding that matter.
Formation
| Attaches to | Form | Example |
|---|---|---|
| Verb (ます-stem) | V(stem) + かねる | わかりかねる / 賛成しかねる |
When: Formal and business-like. It conveys a psychological inability or unwillingness — 'I can't quite bring myself to' — and is a standard polite way to decline (いたしかねます, わかりかねます).
Examples
申し訳ございませんが、こちらでは判断いたしかねます。
I'm very sorry, but we cannot make that decision here.
彼の意見には賛成しかねる。
I find it hard to agree with his opinion.
When you can't use it
- Used for reluctance or unwillingness, not physical impossibility. You wouldn't say 持ち上げかねる for being unable to lift something heavy; that's できない.
Easily confused with
〜かねない Despite both coming from かねる, the meanings flip: かねる = 'cannot do ~' (お答えしかねます = 'I can't answer'), while かねない = 'might (regrettably) do ~' (失敗しかねない = 'might well fail'). This is the classic trap — watch the negative. 〜得ない 得ない denies that something is possible at all ('it can't happen'). かねる is about the speaker's own inability or unwillingness to do something, and is markedly more polite/formal.
See 〜かねる in real sentences
Jengo shows 〜かねる the way you actually meet it: inside real Japanese sentences, so it sticks instead of staying an abstract rule.
Study it in JengoSources Compiled with reference to A Dictionary of Intermediate Japanese Grammar.