In, At, On (Position 3)

Fixed Expressions: in bed, at work, at school

Some common places use a fixed preposition. There is no real choice here — you just need to learn them.

Use in with:

Expression	Example
in bed	Tom called in sick. He’s still in bed.
in hospital	Our colleague had surgery and is in hospital for a few days.
in prison	The man was found guilty and is now in prison.

Use at with:

Expression	Example
at home	I’ll be working at home tomorrow.
at work	She’s at work until 6 p.m. today.
at school	Their son is still at school. He finishes at 3.
at university / at college	My sister is at university studying business.

With home, you can drop at when the verb is be: I’ll be home all day. But keep at when there is an action: Let’s eat at home instead of going out.

At for Events

When somebody is at an event, they are attending it. Use at with parties, meetings, conferences, weddings, concerts, and similar events.

• Were there many people at the meeting this morning?
• I ran into our CEO at a conference last week.
• We saw several clients at the product launch.

In and At for Buildings

For buildings like restaurants, hotels, supermarkets, and offices, both in and at are often possible.

Use at when you talk about what happens there or where an event takes place:

• The quarterly review was held at the Hilton Hotel.
• There was an incident at the warehouse yesterday.
• We had lunch at that new restaurant near the office.

Use at with somebody’s house: I was at David’s house last night. (or simply at David’s)

The same pattern applies to the doctor’s, the hairdresser’s, the dentist’s: She’s at the dentist’s right now.

Use in when you are thinking about the building itself — its rooms, temperature, layout, or physical features:

• It’s always freezing in their office. The heating barely works.
• All the meeting rooms in the hotel have projectors.
• The wifi in the restaurant was terrible.

Compare:

Focus on activity → at	Focus on the building → in
We had dinner at the hotel.	The rooms in the hotel are very small.
I met Lisa at her office.	It’s really noisy in her office.

We also say at the station and at the airport:

• Can you pick me up at the airport?
• There’s a coffee shop at the station.

In for Cities, Towns, and Villages

Use in with cities, towns, and villages:

• Our head office is in London.
• She grew up in a small town in the south.
• The factory is in a village outside Seoul.

Use at only when the place is a stop on a journey:

• Does this train stop at Birmingham?

On and In for Transport

The rule depends on the type of vehicle:

Use on	Use in
on a bus	in a car
on a train	in a taxi
on a plane
on a ship
on a bike / motorbike

Think of it this way: if you can stand up and walk around inside the vehicle, use on. If you sit directly inside a small enclosed space, use in.

• I left my laptop on the train this morning.
• She arrived in a taxi just before the meeting started.
• He cycles to work every day — I often see him on his bike near the bridge.

Quick Self-Check