What are prepositions of place? They are used to indicate the relationship between an object and its location. We use just three key prepositions: in, on, and at.
At
In general, at is used broadly for location, but when referring to objects in relation to places, it usually indicates a specific point or position.
At a point
- Can you see that car at the traffic light?
 - Who is that man at the door?
 
At the top/bottom/end of
- She is at the top of the stairs.
 - Please sign at the bottom of the page.
 - The new café is at the end of the street.
 
At Group activities or events
- We were at the cinema.
 - I didn’t see you at Jackie’s party.
 - We met at a concert.
 
At School, college, university
- He is at school.
 - I’m studying at Oxford University.
 
At home or work
- She’s at home.
 - I’ll be at work all morning.
 
At shops, restaurants, cafés
- I’m at the bakery.
 - If you are at the chemist’s, can you buy some aspirin?
 
In
The word in shows something inside a closed space or area.
In a 3D space
- The book is in the bag.
 - She is waiting in the classroom.
 
In a space with limits or boundaries
- We are in France.
 - I love the houses in the Alps.
 
In a car, water, picture, book
- They are in the car.
 - The kids have fun in the swimming pool.
 - Who’s that woman in the picture?
 - Does it say anything about the concert in the newspaper?
 
On
on indicates something being placed on the surface of something else.
On a surface
- The book is on the table.
 
On the first/second/etc. floor
- The office is on the third floor.
 
On the right/left
- The office is on the third floor on the left.
 
On public transport vehicle
- She’s on the bus/train/plane right now.
 
Something in the media
- I saw it on TV last night.
 - I learned it on the internet.
 

Image source: At, in, on – prepositions of place - Test-English
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