How to say "doing" in Japanese

• 決行けっこうJLPT N1approx.Common
  noun, suru verb, transitive verbCovers 'doing' in the sense of resolutely carrying something out, especially a plan one has resolved on; a common word that stresses going through with the act.
  その会社かいしゃの労働者ろうどうしゃはストを決行けっこうした。↗

  Workers at the company went on a strike.
• こ
  suffixGlossed 'doing; in such a state', this less common abbreviated form is seldom the word you want for 'doing'; treat it as marginal rather than a normal way to express the idea.
• なすって
  expressionA less common, honorific (sonkeigo) 'doing', used for the actions of someone you respect — e.g. politely asking what they are doing. Not a neutral, all-purpose word for 'doing'.
• 差し金さしがね
  nounCovers '(someone's) doing': instigation, suggestion or manipulation — someone putting another up to something. Use it when attributing an outcome to the person behind it, not for 'doing' in general.

Choose by sense: 決行 is doing a plan with resolve, 「なすって」 is respectful 'doing' for a superior's actions, 「差し金」 is someone's (instigating) doing, and 「こ」 is a marginal abbreviated form you will rarely need.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• 決行けっこうdoing (with resolve)
• こdoing
• なすってdoing
• 差し金さしがねinstigation