A1Prepositions

At, in, on: time

Use at, on, and in with different kinds of time expressions. Learning the main time groups makes the choice much easier.

Overview

What this grammar does

Use at, on, and in with different kinds of time expressions. Learning the main time groups makes the choice much easier.

Form and rules

How it works

Use at with clock times and precise points in time: at 7:30, at noon, at midnight, at night.

Use on with days and dates: on Monday, on Friday morning, on 10 May.

Use in with months, years, seasons, centuries, and parts of the day: in July, in 2026, in winter, in the morning.

Do not use at/in/on before this, last, next, every, today, tomorrow, or yesterday: next week, every Monday.

Some fixed expressions must be learned as chunks: at the weekend (common British English), on the weekend (common American English).

A closer look

Meaning and use

Use at for exact clock times and some fixed points, on for days and dates, and in for months, years, seasons, parts of the day, and longer periods.

Common fixed expressions include at night, at the weekend (BrE), in the morning, on Monday morning, and at 7 o'clock.

Examples

See the pattern in complete sentences

at 6:30

on Friday

on Monday morning

in December

in the evening

Common mistakes

What to avoid

in Monday

on Monday

Days use on.

on 7:30

at 7:30

Exact clock times use at.

Ready to practise?

The test combines multiple choice, gap completion, error correction, and sentence building so students have to recognise and produce the grammar, not simply reread the rule.

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