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Quadruple VS

Synonym Boundary: "します", "行う", "〜てしまう", "敝蓋不棄"

All represent the core concept "do", but require precise selection.

Japanese Option A

します

します (shimasu)
N5 / CEFR
Japanese Option B

行う

おこなう (okonau)
N4 / CEFR
Japanese Option C

〜てしまう

〜てしまう (te shimau)
N3 / CEFR
Japanese Option D

敝蓋不棄

へいがいふき
C2PLUS / CEFR

Quadruple VS Nuance Contrast & Social Differences

When expressing "do" in Japanese, you must carefully distinguish between "します", "行う", "〜てしまう", "敝蓋不棄" based on context.
  • します (します (shimasu) - Level: N5): Maps to "to do, to make, to play (a sport)" and is used when 非常に多用途な動詞です。「〜をします」の形で、行動、スポーツ、仕事など様々な活動を表します。/ A very versatile verb. Used in the form '~をします' to express various activities, sports, or jobs..
  • 行う (おこなう (okonau) - Level: N4): Maps to "to do, to conduct, to carry out, to perform" and is used when More formal than する. Typically used for conducting events, ceremonies, research, or official procedures..
  • 〜てしまう (〜てしまう (te shimau) - Level: N3): Maps to "to do completely; to do regrettably/unintentionally" and is used when Expresses either the completion of an action, often implying 'finished doing,' or an action done unintentionally or regrettably. In casual speech, it's often shortened to 〜ちゃう/〜じゃう.
  • 敝蓋不棄 (へいがいふき - Level: C2PLUS): Maps to "do not discard a worn-out lid; a metaphor for valuing old things or long-standing friendships" and is used when Essential structural term in CEFR C2PLUS vocabulary syllabus..
Mixing these up can easily lead to unnatural translations. Refer to the bilingual context cards below to master the boundaries!
Context for "します"
毎日宿題をします。
I do my homework every day.
Context for "行う"
今日は会議が行われる予定だ。
A meeting is scheduled to be held today.
Context for "〜てしまう"
大事な書類をなくしてしまいました。
I accidentally lost important documents.
Context for "敝蓋不棄"
私は敝蓋不棄に興味があります。
I am interested in do not discard a worn-out lid; a metaphor for valuing old things or long-standing friendships.

Synonym Mastery Challenge

Which Japanese word perfectly fits this blank space?

Fill in the blank: "毎日宿題を ___ 。" (Meaning: "I do my homework every day.")
🎉 Correct Answer!

Remember: "します" is correct here because it represents "to do, to make, to play (a sport)" in the context: "I do my homework every day.".

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