Prepositions of Time — English Grammar Exercises

Prepositions of Time: Quick Reference

English uses different prepositions depending on whether you're talking about a precise point in time, a day, or a longer period.

At, On, In — The Core System

• at — precise points: at 5 o'clock, at midnight, at noon, at night
• on — days and dates: on Monday, on 15th March, on Christmas Day
• in — longer periods: in September, in 2024, in winter, in the morning

Duration and Starting Points

• for — how long: for three years, for an hour
• since — when it started: since 2020, since Monday
• during — within an event: during the meeting (+ noun)
• while — at the same time: while I was sleeping (+ clause)

Deadlines

• until — action continues up to: wait until 5 pm
• by — must be done before: finish by Friday

Common Mistakes

Also Practice