Many learners know a lot of English words but still hesitate over a tiny word before a time: is it in Monday or on Monday? Is it since two years or for two years? Prepositions of time are small, but they tell the listener exactly how an event connects to time. In this lesson you will learn ten of them at A2 level. Each one has a meaning, two example sentences and a usage note.
Why time prepositions matter
A time preposition shows whether something happens at a exact moment, on a day, over a period, or before a deadline. If you choose the wrong one, people often still understand you, but your sentence sounds unnatural. Sometimes the meaning really changes, as with by and until.
We will study them in four groups: points in time (at, on, in), length of time (for, since, during), deadlines and limits (by, until), and order (before, after).
The big three: at, on and in
Think of a funnel. At is for exact moments, on is for days and dates, and in is for longer periods such as months and seasons.
1. at
Meaning: We use at for clock times and exact moments, and in some fixed phrases.
- The class starts at 9 o’clock.
- I usually sleep at night.
Usage note: We say at night, at noon and at midnight. For the days off, British English says at the weekend and American English says on the weekend.
2. on
Meaning: We use on for days of the week and dates, and for parts of a specific day.
- We have a meeting on Monday.
- Her birthday is on 5 May.
Common mistake: in Monday. The correct form is on Monday. We also say on Friday morning, because the day is specific.
3. in
Meaning: We use in for months, seasons, years and general parts of the day.
- It is very hot in July.
- I study in the morning.
Usage note: We say in the morning, in the afternoon and in the evening, but not at the morning. For night, we say at night.
Length of time: for, since and during
These three words cause many mistakes, because many learners translate them from their first language.
4. for
Meaning: For comes before the length of a period: two hours, a week, three years.
- I waited for two hours.
- She has lived here for three years.
Common mistake: She has lived here since three years. The correct form is for three years, because three years is an amount of time, not a starting point.
5. since
Meaning: Since comes before the starting point of a period in the past. It is usually used with the present perfect.
- I have known him since Monday.
- They have worked here since March.
Common mistake: I know him since Monday. The correct form is I have known him since Monday.
6. during
Meaning: During means while something is happening. It is followed by a noun for an event or a period, not by a number of hours or days.
- Please be quiet during the film.
- We visited my aunt during the summer.
Usage note: We do not say during two hours. We say for two hours. Use during with a known event or period, such as the lesson or the holiday.
Deadlines and limits: by and until
These two words look similar, but they have different meanings.
7. by
Meaning: By means at that time or before it. It gives a deadline.
- Please send the report by Friday.
- I must be home by 10 o’clock.
Usage note: By goes with a single action that must be finished before or at a certain time.
8. until
Meaning: Until means that something continues up to a time and then stops.
- I will wait until 6 o’clock.
- The shop is open until Friday.
Common mistake: I will finish the work until Friday. The correct form is by Friday, because finishing is one action with a deadline. Waiting is a continuing action. In everyday speech, till can replace until.
Order: before and after
9. before
Meaning: Earlier than a time or another event.
- I drink coffee before breakfast.
- Call me before you leave.
Usage note: Before can be followed by a noun (breakfast) or by a full clause (you leave).
10. after
Meaning: Later than a time or another event.
- We go for a walk after dinner.
- She called me after the class.
Usage note: Do not use will inside the time clause. Say I will call you after I arrive, not after I will arrive.
Quick review table
| Word | Use | Example |
|---|---|---|
| at | clock time, exact moment | at 7 o’clock |
| on | day, date | on Monday |
| in | month, season, part of day | in July |
| for | length of time | for two hours |
| since | starting point | since Monday |
| during | while an event happens | during the film |
| by | deadline | by Friday |
| until | continues up to a time | until 6 o’clock |
| before | earlier than | before breakfast |
| after | later than | after dinner |
Common mistakes and corrections
- Wrong: I will see you in Monday. Right: I will see you on Monday.
- Wrong: We meet at the morning. Right: We meet in the morning.
- Wrong: I live here since two years. Right: I have lived here for two years.
- Wrong: He worked during three hours. Right: He worked for three hours.
- Wrong: Send it until Friday. Right: Send it by Friday.
How to practise step by step
- Write three sentences about your day: one with at, one with in the morning, and one with on and a day of the week.
- Before you use for or since, ask: do I have a length of time or a starting point?
- Before you use by or until, ask: is this a deadline or an action that continues up to a time?
- Write two sentences with before and after about your daily habits.
- Read your sentences aloud and check that each preposition fits.
Memorising the list is not enough. Use these phrases in sentences about your real life until they feel automatic.