English grammar
Prepositions of time: at, on and in 📕
English uses three main prepositions for time. Think of them as going from small to big.
| Preposition | Used with | Examples |
| at | exact times, short moments | at 7 o'clock, at noon, at night, at the weekend |
| on | days and dates | on Monday, on 17 May, on my birthday, on Friday morning |
| in | longer periods | in June, in 2025, in the summer, in the morning |
Examples
The class starts at nine.
I was born on 3 April.
We go on holiday in July.
No preposition
We do not use at, on or in before this, next, last, every, today, tomorrow, yesterday.
✓ I'll see you next week.
✗ I'll see you on next week.
✓ I work every Saturday.
In the morning, but on Monday morning
in the morning / in the afternoon / in the evening
on Monday morning / on Friday evening
at night
✗ I start work in 8 o'clock.
✓ I start work at 8 o'clock.