in, on, and at: prepositions of place, and prepositions of time

in / on / at
Prepositions of place and time

The prepositions in, on, and at are very common English words. They are used when talking about a place or time. They have basic meanings and can be used in a wide range of situations.

So first, what do they mean?

Where? Adding a place

  • in a boundary: Where the area starts and ends IS important.
prepositions of place diagram with pictures and examples. "in". In the (room). In (space). In (state). In (country).
  • on a surface: Where the area starts and ends IS NOT important.
prepositions of place diagram with pictures and examples. "on". On (floor of building). On (surface of object). On (surface-material). On (form of transport).
  • at a point in space
  • at an event
prepositions of place diagram with pictures and examples. "at". At (place). At (location). At (event).

Examples: saying where

Look at these examples and visualize where.

I’m in the supermarket.
He plays guitar in the bedroom.
I wash my hair in the shower.
I live in Texas.
They like wine in France.

I’m on the 4th floor.
Dinner is on the table.
The bus is on the road.
She reads books on the bus.

I work at the supermarket.
I’m at the bus stop.
We’re at yoga.
I’m at the concert.

When? Adding a time

We can’t see time, so we visualize when the same way as we visualize where.

We use in, on, and at to say when something is or happens.

  • in: When the period of time starts and ends IS important.
prepositions of time diagram with pictures and examples. "in". In (time of day). In (season). In (year). In (month).
  • on: When the period of time starts and ends IS NOT important.
prepositions of time diagram with pictures and examples. "on". On (day of the week). On (date). On (special day).

(We think of a day as being the time from when we wake up to the time we go to sleep. Exactly when a person wakes up and goes to sleep is not important.)

  • at a point in time.
  • at an event in time.
prepositions of time diagram with pictures and examples. "at". At (time of day). At (named time-noon, midnight). At (event in time - sunset, night).

Examples: saying when

Look at these examples and visualize when.

I have breakfast in the morning.
She plays guitar in the afternoon.
I wash my hair in the evening.
We ski in winter.
They travel in spring.
We swim in summer.
We hike in fall.
Christmas is in December.
I finish high school in 2025.

I study English on Monday.
We celebrate the new year on December 31st.
We sleep on New Year’s Day.

I start work at 10am.
They have lunch at noon.
He walks the dog at sunset.
I sleep at night.

Key Point

Think about what in, on and at mean and why they are used.
It may be very different to how you talk about time and place in you first language.

Practice

Many students find these prepositions confusing because the keep given rules for when to use each one. “You should say in the…” but “at the…” I think it is hard to remember all of these uses. And the thing is, they don’t happen all the time! We can say, “I work at a shop” or “I work in a shop”.

But when it makes sense, it is easier to remember. So the key is to change the way you think about prepositions. What does it mean? Does it clearly communicate the what I’m thinking?

Thinking about the meanings helps you see patterns and discover why we use these prepositions the way you do. When you think first about meaning and then explore how prepositions are used, you see why people are comfortable using them this way and it all makes a lot of sense.

Common questions

Why do we use on for days?

“on the weekend” or “at the weekend?”

Key Point

There are different words that people use.

  • Sometimes these words have different meanings.
  • Sometimes (like with on the weekend or at the weekend) either way makes sense and people simply use what they are used to.

People use words because words have meaning. This is true for vocabulary and it is true for grammatical words and parts of words too, including parts of words for tenses and parts added to nouns.

Looking for a good grammar book?

Grammar helps people understand each other better.

If you are interested in a grammar book that looks at common parts of English sentences and what they mean (like in, on, and at), be sure to check out Real Grammar.

With Real Grammar you understand grammatical meaning. Grammatical meaning helps you understand more of what people say in English.

Real Grammar is grammar for communication.

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