Usage of ～おき
The suffix ～おき is used to express a regular interval or spacing between events or items, meaning "after every ~" or "every ~". It attaches to a time unit, number, or counter to indicate frequency or spacing.
Common contexts
You often see ～おき in schedules, transportation timetables, cleaning routines, or any situation where something happens at regular intervals. For example, "10分おき" means "every 10 minutes".
Collocations and patterns
- 数字 + おき: Indicates the interval, e.g., 5分おき (every 5 minutes), 3日おき (every 3 days).
- 週に一回おきに: every other week (literally "every one week interval").
Register and nuance
～おき is neutral and commonly used in both spoken and written Japanese. It is straightforward and factual, without implying any emotional nuance.
Common learner mistakes
Do not confuse ～おき with ～ごとに, which also means "every ~" but can have slightly different nuance or usage. ～おき emphasizes spacing or intervals, while ～ごとに can emphasize repetition or occurrence at each unit. For example, "10分おきに" focuses on the interval between events, while "10分ごとに" can be used similarly but sometimes stresses each occurrence.
Understanding this subtle difference helps in choosing the right expression.