꼭 기억할 핵심
작은 단위에서 큰 단위로: 시각은 at, 요일·날짜는 on, 월·연도 같은 긴 기간은 in.
01at: points on the clock
Use at for precise points: clock times, mealtimes treated as points, and festival moments. At 7 o'clock, at noon, at midnight, at night, at Christmas — each one answers the question exactly when. Think of at as a pin dropped on the timeline.
The meeting starts at 10 a.m.
at + clock time
The meeting starts at 10 a.m.
02on: days and dates
Use on for days of the week and calendar dates: on Monday, on May 1st, on Christmas Day. When a date includes the day, on wins — on Monday morning, on the weekend (American) — because the day is the anchor. If you can circle it on a calendar page, reach for on.
Her birthday is on May 1st.
on + date
Her birthday is on May 1st.
03in: longer stretches
Use in for months, seasons, years, and parts of the day: in July, in summer, in 2026, in the morning. These are containers of time rather than points — you are somewhere inside the period. Centuries and decades follow the same logic: in the 1990s.
Watch the famous pair: arrive on time means punctual, while arrive in time means early enough to do something — in time for dinner, in time to help. And drop the preposition entirely before this, last, next, every, yesterday, and tomorrow: see you next Monday, not on next Monday.
She was born in 2019.
in + year
She was born in 2019.
04Try a week of your life
Write seven lines about your week using all three: at 7:30, on Tuesday, in the evening. Then add one deadline with by — finish this by Friday — and notice how by means no later than, not at that moment. Keeping your own examples next to each other makes the small-to-big picture stick.
이제 당신 차례
연결해 보세요.
고르기 전에 상황을 먼저 읽으세요. 이유가 답만큼 중요합니다.
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