This is the 408th most frequent Korean word.
일
The Korean word "일" can mean "work," "job," "task," or "day," depending on context.
Here, '일' means 'task' or 'matter' and refers to an activity or responsibility.
내일 중요한 일이 있어요.
I have an important task tomorrow.
In this context, '일' is part of '일교차,' where it relates to 'day' in describing temperature differences throughout a single day.
오늘 날씨가 정말 일교차가 커요.
Today the temperature difference is really large.
Here, '일' translates to 'work' or 'labor,' indicating effortful activity.