B1 Intermediate Perfect and past tenses
for and since
Lesson goal. After this lesson you can use for and since correctly to say how long something has lasted.
When to use it
- Saying how long: I have lived here for five years.
- Saying when it started: I have lived here since 2019.
- Answering How long…?
Form
| Word | Used with | Example |
|---|---|---|
| for | period of time (how long) | for two hours · for a week · for ages |
| since | starting point (since when) | since Monday · since 2019 · since I was ten |
| since + clause | the clause is in the past simple | since I moved here |
Step by step
- Look at the time phrase that follows.
- It answers how long? (two years, a month) → for.
- It answers starting when? (2019, Monday, I was ten) → since.
- Remember: both normally go with the present perfect, not the present simple.
Converting between the two
| With for | With since | Note |
|---|---|---|
| for three years | since 2023 | if it is now 2026 |
| for two hours | since two o'clock | if it is now four o'clock |
| for a long time | since I was a child | same idea, different way of measuring |
Examples
I have studied English for six years.
I have studied English since grade 4.
She has been ill for a week.
We haven't met since last summer.
They have been married since 2015.
He has been waiting for twenty minutes.
Common mistakes
I have studied English since five years. → I have studied English for five years.
five years is a length, not a point. Vietnamese uses one word for both, so learners pick since.
They have lived there for 2018. → They have lived there since 2018.
A year is a point → since.
I live here for three years. → I have lived here for three years.
An action that began in the past and still continues needs the present perfect, not the present simple.
Memory tip
Question the time phrase. If it answers “How long?” use for. If it answers “Starting when?” use since.
Summary
- for + a duration · since + a starting point.
- A clause after since takes the past simple.
- Both normally go with the present perfect.
Practise this lesson
Do exercises with an explanation for every question, take mini tests and track your progress on GrammUp.