For & Since with Present Perfect TenseWe often use for and since with the present perfect tense. - We use for to talk about a period of time - 5 minutes, 2 weeks, 6 years.
- We use since to talk about a point in past time - 9 o'clock, 1st January, Monday.
| for | since | | a period of time | a point in past time |
| x------------ | | 20 minutes | 6.15pm | | three days | Monday | | 6 months | January | | 4 years | 1994 | | 2 centuries | 1800 | | a long time | I left school | | ever | the beginning of time | | etc | etc |
Here are some examples: - I have been here for 20 minutes.
- I have been here since 9 o'clock.
- John hasn't called for 6 months.
- John hasn't called since February.
- He has worked in New York for a long time.
- He has worked in New York since he left school.
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| For can be used with all tenses. Since is usually used with perfect tenses only. |
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Now check your understanding » |
