I. Preposions of Time - AT / IN / ON
The preposition AT is used in the following descriptions of time:
1. With clock times
- My last train leaves at 10:30.
- We left at midnight.
- The meeting starts at two thirty.
- With specific times of day, or mealtimes
- He doesn’t like driving at night.
- I’ll go shopping at lunchtime.
2. With festivals
- Are you going home at Christmas/Easter?
3. In certain fixed expressions which refer to specific points in time
- Are you leaving at the weekend?
- He’s unavailable at present.
- I finish the course at the end of April.
The preposition IN is used in the following descriptions of time:
1. With months, years, seasons, and longer periods of time
- I was born in 1965.
- We’re going to visit them in May.
- The play is set in the Middle Ages.
2. With periods of time during the day
- He’s leaving in the morning.
- She usually has a sleep in the afternoon.
- I tried to work in the evening.
3. To describe the amount of time needed to do something
- They managed to finish the job in two weeks.
- You can travel there and back in a day.
4. To indicate when something will happen in the future:
- She’ll be ready in a few minutes.
- He’s gone away but he’ll be back in a couple of days.
The preposition ON is used in the following descriptions of time:
1. With days of the week, and parts of days of the week
- I’ll see you on Friday.
- She usually works on Mondays.
- We’re going to the theatre on Wednesday evening.
2. With dates
- The interview is on 29th April.
- He was born on February 14th, 1995.
3. With special days
- She was born on Valentine’s Day.
- We move house on Christmas Eve.
- I have an exam on my birthday.
II. Prepositions of Place - AT / IN / ON
The preposition AT is used in the following descriptions of place/position:
1. With specific places/points in space
- She kept the horse at a nearby farm.
- Angie’s still at home.
- I’ll meet you at reception.
2. With public places and shops
- Jane’s at the dentist/hairdresser.
- I studied German at college/school/university.
- Shall I meet you at the station?
3. With addresses
- They live at 70, Duncombe Place.
4. With events
- I met her at last year’s conference. She wasn’t at Simon’s party.
The preposition IN is used in the following descriptions of place/position:
1. With geographical regions
- Driving in France is very straightforward.
- With cities, towns and larger areas
- Do you like living in Nottingham?
2. With buildings/rooms and places that can be thought of as surrounding a person or object on all sides
- Can you take a seat in the waiting room, please?
- I’ve left my bag in the office.
- There’s a wedding in the church this afternoon.
3. With containers
- There’s fresh milk in the fridge.
- I think I’ve got a tissue in my pocket.
- The money is in the top drawer of my desk.
4. With liquids and other substances, to show what they contain
- Do you take milk in your coffee?
- I can taste garlic in this sauce.
- There’s a lot of fat in cheese and butter.
The preposition ON is used in the following descriptions of place/position:
1. With surfaces, or things that can be thought of as surfaces
- The letter is on my desk.
- There was a beautiful painting on the wall.
- The toy department is on the first floor.
2. With roads/streets, or other things that can be thought of as a line, e.g. rivers
- The bank is on the corner of King’s Street.
- Bournemouth is on the south coast.
- It’s the second turning on the left.