In, on, and at are the most common prepositions for time and place in English.

For TIME

IN (longer periods)

• Months: in January, in March
• Years: in 2024, in 1999
• Seasons: in summer, in winter
• Parts of day: in the morning, in the afternoon, in the evening
• Note: NOT "in the night" — use at night

ON (days and dates)

• Days: on Monday, on Friday
• Dates: on March 15th, on New Year's Day
• Special days: on my birthday, on Christmas Day

AT (specific times)

• Clock times: at 3:00, at 7:30
• Specific moments: at noon, at midnight
• Fixed expressions: at night, at the weekend (UK)

Quick Test for Time

• General period (month/year) → IN
• Specific day → ON
• Exact time → AT

For PLACE

IN (enclosed spaces, areas)

• Countries/Cities: in Japan, in Paris
• Buildings: in the house, in the office
• Containers: in the box, in my pocket

ON (surfaces, lines)

• Surfaces: on the table, on the wall
• Floors: on the second floor
• Transportation: on the bus, on the train, on the plane
• Streets: on Main Street

AT (specific points, locations)

• Addresses: at 123 Main Street
• Locations: at the bus stop, at the door
• Places as points: at school, at work, at home

Examples by Level

Time:

• A2: I wake up at 7:00 in the morning.
• A2: My birthday is on June 15th.
• B1: I started working here in 2020 on a Monday.

Place:

• A2: The book is on the table in the living room.
• B1: We met at the café on the corner in the city center.

Special Cases

Transportation:

• IN for cars: in the car, in a taxi
• ON for public transport: on the bus, on the train

Arrive:

• arrive in a city/country
• arrive at a specific place

Common Mistakes

❌ I'll see you on 3:00. ✅ I'll see you at 3:00.

❌ My birthday is in March 15th. ✅ My birthday is on March 15th.

❌ I'm on the car. ✅ I'm in the car.

FAQs

Q: "In the weekend" or "at the weekend"? A: "At the weekend" (British). "On the weekend" (American).

Q: "In the morning" but "at night" — why? A: Fixed expressions. English isn't always logical.

Q: How do I remember all of these? A: Think: IN = inside/longer period, ON = surface/day, AT = point/time.