Master English Grammar

Prepositions of Time – At, On, In

Learn how to use prepositions of time such as at, on, and in to describe when something happens.

What Are Prepositions of Time?

Prepositions of time are used to indicate when something happens. The most common ones are at, on, and in.

Why Is This Important?

Using the correct preposition of time helps make your sentences more precise and grammatically correct.

Key Points

Use 'at' for specific times
- at 7:00 PM
- at midnight
Use 'on' for specific days and dates
- on Monday
- on July 4th
Use 'in' for longer periods (months, years, centuries)
- in January
- in 2020

Rules for Using Prepositions of Time
Use 'at' for exact times, holidays without 'day', and certain phrases.
We will meet at 6 PM.
She was born at midnight.
He visits his family at Christmas.
Use 'on' for specific days, dates, and special occasions.
We have a meeting on Monday.
My birthday is on April 10th.
They got married on Valentine's Day.
Use 'in' for months, years, centuries, and longer periods.
She was born in May.
The company was founded in 1999.
A lot changed in the 20th century.
Special Cases & Exceptions:
Some time expressions do not follow these rules.
Some common phrases do not use these prepositions.
Incorrect: I will see you in next week.
Correct: I will see you next week.

Example	Tense	Use
I have a meeting at 3 PM.	At	Specific time
We met on Monday.	On	Specific day
She was born in July.	In	Longer period

Quick Examples

Here are quick examples of prepositions of time in use.

Learn More with Video Lessons

Disclaimer: I am not affiliated with the creators of these videos. These are publicly available resources used to provide additional information on the topic.