Virtuous English AcademyPresent Perfect: For and Since (A2)
- #A2
- #Grammar
- #Rules
- #Examples
For describes a length of time and since describes a starting point, and both are used with the present perfect. This lesson makes the difference clear so you can talk about how long things have lasted.
For and since both answer the question how long? and both appear constantly with the present perfect, but they measure time in completely different ways. For measures a length of time — for three years, for ten minutes. Since names a starting point — since 2019, since Monday, since I moved here.
The test is simple and never fails. If the words after the preposition describe a duration, use for. If they name a moment when something began, use since. For six months and since June can describe exactly the same period, but they express it from opposite directions.
Both are used with the present perfect because that tense is what English uses for a situation that began in the past and is still true now. I have worked here for two years means I still work here. Switching to the past simple — I worked here for two years — would mean the job is over, which is a genuinely different statement.
How to form For and Since
| Preposition | Followed by | Examples |
|---|---|---|
| for | a period of time | for two hours, for a week, for ages |
| for | a number + time unit | for three years, for six months |
| since | a clock time or date | since nine o'clock, since 5 May |
| since | a day, month or year | since Monday, since June, since 2020 |
| since | an event | since I left school, since we met |
| since | a general past point | since then, since childhood |
For and Since: the key rules
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For + a length of time: for two years, for ten minutes, for ages.
We've lived here for six years.
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Since + a starting point: since 2019, since Monday, since I was a child.
She's worked there since January.
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How long…? questions expect a for/since answer with the present perfect.
How long have you known him? — Since university.
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The action or state continues to now — that is why the present perfect, not the past, is used.
I've had this phone for three years (and I still have it).
When to use For and Since
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How long you have done something
Jobs, homes, relationships and study — anything continuing from the past into now.
I've worked here for five years. She's lived here since 2018.
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Answering How long questions
The standard question form, answered with either preposition depending on how you frame it.
How long have you known him? — For about ten years.
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Describing something that has not happened
Negatives with for and since are very common and often carry mild complaint.
I haven't seen her for months. We haven't spoken since the meeting.
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Since with a clause
Since can introduce a whole clause naming the starting event, usually in the past simple.
I've felt better since I changed jobs.
for vs. since
Ask yourself whether the time expression measures a length or names a beginning.
for — a length of time
How long the situation has lasted. Works with any duration, long or short.
for two days, for a long time, for twenty years
since — a starting point
When the situation began. Works with dates, times, days and past events.
since Tuesday, since 2015, since I was a child
For and Since in example sentences
- We've lived in this house for eleven years.for + a duration.
- We've lived in this house since 2015.since + a starting year — same period, framed differently.
- I haven't eaten since breakfast.since + a past event.
- She's been ill for a week.for with a short duration.
- How long have you studied English?The standard question that for and since answer.
- They haven't visited us for ages.for ages is a common informal duration.
- He's been much happier since he moved.since introducing a past simple clause.
- I've known her since university.since + a period of life as a starting point.
For and Since in a real conversation
Every for measures a length and every since names a beginning — check each one as you read.
Doctor:How long have you had this pain?
Patient:For about three weeks. It started after a long flight.
Doctor:Have you taken anything since then?
Patient:I've taken painkillers since Monday, but they haven't helped.
Doctor:Have you been sleeping badly for long?
Patient:Since the pain began, really. I haven't slept properly for a fortnight.
Common mistakes (and how to fix them)
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I live here since 2020.
I've lived here since 2020.
A period continuing to now takes the present perfect, not the present simple.
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She's been ill since three days.
She's been ill for three days.
Three days is a duration → for; since needs a starting point.
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We've known each other for we were kids.
We've known each other since we were kids.
A clause marking the start ('we were kids') takes since.
Practise For and Since today
Practise converting between the two — the same fact stated both ways.
- Write six sentences about your life using for, then rewrite each one using since.
- Answer these with both prepositions: How long have you lived in your home?
- Complete these: ___ 2019, ___ two months, ___ I was ten, ___ ages, ___ last Friday.
- Write four negative sentences about things you haven't done for a long time.
For and Since: frequently asked questions
Can I use for and since with the past simple?
For works with the past simple when the period is completely finished: I lived in Rome for three years, meaning I no longer live there. Since almost never works with the past simple, because since inherently connects a past starting point to the present, which is exactly what the present perfect expresses. If you find yourself writing since with a past simple main verb, the tense is probably wrong.
Why is I am here since Monday wrong?
Because the present simple describes only the current moment and carries no sense of duration reaching back into the past. English requires the present perfect for a situation that began earlier and continues now: I have been here since Monday. This is one of the most common transfer errors, since many languages including German, French, Italian and Turkish use a present tense in exactly this situation.
What is the difference between for ages and for a long time?
They mean the same thing, but for ages is informal and often slightly exaggerated, while for a long time is neutral and works in any register. I haven't seen him for ages usually means a few months rather than literally a very long period. In formal writing prefer for a long time or a specific duration.
Does since always need the present perfect?
In its time meaning, yes — the main verb takes the present perfect while the clause after since usually takes the past simple: I've been calmer since I stopped commuting. Note that since has a second meaning of because, as in Since you're here, let's start, and in that use it has nothing to do with tense at all. Context makes the two apart easily.