Prepositions of Time
A1 · BeginnerPrepositionsAt 9 o'clock, on Monday, in March — the three time prepositions follow a simple, learnable pattern.
What you'll learn
- at is for clock times and a few fixed expressions: at 9 o'clock, at night, at the weekend
- on is for days and dates: on Monday, on March 5th, on my birthday
- in is for longer periods: in March, in 2020, in the morning, in winter
- A few expressions break the pattern and just need to be memorized
Three prepositions, three sizes of time
English uses three main prepositions to talk about time: at, on, and in. A useful way to think about them is by size — at for a precise point in time, on for a specific day or date, and in for a longer period like a month, year, or season.
at for precise points in time
Use at for clock times and a small set of fixed time expressions that behave like a single point: at 9 o'clock, at noon, at midnight, at night, and at the weekend (in American English, usually on the weekend).
on for days and dates
Use on for specific days of the week, dates, and named single days: on Monday, on March 5th, on my birthday, on New Year's Day.
in for longer periods
Use in for months, years, seasons, centuries, and parts of the day (except night): in March, in 2020, in summer, in the 21st century, in the morning.
Real English
Watch out
Clock times always take at, never on.
Months take in, not at — in is for longer periods like months, years, and seasons.
Specific days of the week take on, not in.
Real life — Planning a visit
"When are you free this week?"
"I'm busy in the mornings, but I'm free at 3 on Wednesday."
"Perfect — let's meet at the café at 3, on Wednesday, then."
"Sounds good — see you then!"
Practice
Exercise 1 · Choose the correct preposition
The meeting is ___ 9 o'clock.
Exercise 2 · Choose the correct preposition
Her birthday is ___ March.
Exercise 3 · Choose the correct preposition
We're having a party ___ Saturday.
Exercise 4 · Choose the correct preposition
I usually get up ___ 7 a.m.
Exercise 5 · Choose the correct preposition
It gets dark early ___ winter.
Exercise 6 · Choose the correct preposition
I'll see you ___ Christmas Day.
Exercise 7 · Choose the correct sentence
Choose the correct sentence.
Exercise 8 · Choose the correct preposition
We always visit my grandparents ___ the weekend.
Exercise 9 · Complete the sentence
Fill in the correct preposition: The shop opens ___ 8:30.
Exercise 10 · Complete the sentence
Fill in the correct preposition: My flight leaves ___ the morning.
Exercise 11 · Sort the time expressions into groups
0 / 8 sorted
Quick challenge
Five quick questions to check what stuck.
Question 1 / 5
Score: 0/0
The shop closes ___ 6 p.m.
You learned
- at is for precise points in time: at 9 o'clock, at night, at the weekend.
- on is for days and dates: on Monday, on March 5th, on my birthday.
- in is for longer periods: in March, in 2020, in summer, in the morning.
- A few fixed expressions (at night, at the weekend) don't follow the size pattern and need to be memorized.
Related grammar lessons
Prepositions of Place
Learn when to use in, on, and at to talk about location in English — enclosed spaces, surfaces, and specific points each take their own preposition.
Prepositions of Movement
Learn prepositions that describe direction and movement — into, onto, through, across, along, over, and towards — and how each one shows a different path.
Dependent Prepositions
Understand what a 'dependent preposition' is — a fixed preposition that a particular verb, adjective, or noun always takes, with no logical rule to predict it.
Verb + Preposition
Learn the fixed prepositions that go with common verbs like listen to, wait for, depend on, and apologize for — each verb has its own required partner.