〜かねない

Expresses the speaker's worry that a bad result is quite possible — 'there's no telling that it won't happen'. It attaches to the ます-stem and only takes negative outcomes, so 合格しかねない is wrong. Often used to warn about someone's behaviour or about a situation left unchecked. Do not confuse it with 〜かねる, which means 'cannot (bring oneself to) do' and is polite refusal language.

• そんな運転をしていると、事故を起こしかねないよ。

  そんなうんてんをしていると、じこをおこしかねないよ。

  If you drive like that, you could well cause an accident.

• 働きすぎは、体を壊しかねない。

  はたらきすぎは、からだをこわしかねない。

  Working too much could well ruin your health.

• あの人なら、平気でうそをつきかねない。

  あのひとなら、へいきでうそをつきかねない。

  Someone like him might well tell a lie without batting an eye.