~を契機に— Seizing the Turning Point
を契機に (or を契機として) is the formal, written counterpart of をきっかけに, marking an event as the opportunity or turning point that triggers a significant change. It is used for weightier, often societal or life-defining occasions such as retirement, disasters, or reforms. The following clause states the resulting change.
Grammar path · 練習
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A short lesson: the pattern, its sentence anatomy, a quick quiz and a sentence to build.
Structure · 形
[Noun / plain-form + の] + を契機に(して)/を契機として
Examples · 例文
定年退職を契機に、田舎で暮らすことにした。
Teinen taishoku o keiki ni, inaka de kurasu koto ni shita.
Taking the opportunity of retirement, I decided to live in the countryside.
定年退職を契機に marks retirement as the significant turning point.
この事件を契機として、法律が改正された。
Kono jiken o keiki to shite, houritsu ga kaisei sareta.
Triggered by this incident, the law was amended.
を契機として presents the incident as the formal catalyst for reform.
震災を契機に、防災意識が高まった。
Shinsai o keiki ni, bousai ishiki ga takamatta.
The earthquake disaster prompted a rise in disaster-preparedness awareness.
震災を契機に marks the disaster as the pivotal triggering event.
Usage notes · 注意
- Register: formal and written; used for weighty or societal turning points.
- 契機 (けいき) literally means 'opportunity/turning point'.
- After a clause, nominalize with の before を契機に.
Commonly confused with
The JLPT rarely asks whether you recognise a pattern — it asks which of several similar patterns fits. These are the ones ~を契機に is tested against.
vs~をきっかけに
をきっかけに is everyday and works for small personal triggers, while を契機に is formal and reserved for significant, weighty turning points.
vs~に際して
に際して means 'on the occasion of (doing something)' and looks forward to an event, whereas を契機に marks an event as the cause of a resulting change.
More formal expressions
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