不ふ完かん全ぜん燃ねん焼しょう

noun, noun or participle which takes 'suru'

incomplete combustion; imperfect combustion

Technical term for fuel not burning completely, producing soot or carbon monoxide. Also used metaphorically.

• 不ふ完かん全ぜん燃ねん焼しょうを起おこすと一いっ酸さん化か炭たん素そが発はっ生せいする。

  Incomplete combustion produces carbon monoxide.

noun, noun or participle which takes 'suru'

not giving one's all; falling short; underperforming

Idiomatic use describing a person or effort that fails to achieve full potential, often due to lack of effort or poor conditions. Common in sports, work, and personal achievement contexts.

• 今日きょうの試し合あいは不ふ完かん全ぜん燃ねん焼しょうだった。

  Today's game felt like we didn't give it our all.

• 不ふ完かん全ぜん燃ねん焼しょうで終おわらないように全ぜん力りょくを尽つくす。

  I'll give it everything so I don't end up feeling like I held back.