Present perfect and ‘for’/’since’
Meaning and use
The present perfect is often used to talk about situations that started in the past and are continuing now. We sometimes use the present perfect in a question with how long to ask about how long a present situation has continued.
How long have Sasha and Tanya been married?
We talk about how long using the words for and since.
For = throughout (a period of time).
They’ve been married for six months.
Since = from (an exact point in time) until now.
They’ve been married since March.
We can also use present perfect + since + past simple.
I haven’t seen Tanya since we graduated.
The present perfect is made with subject + have/has (positive) or haven’t/hasn’t (negative) + past participle.
For is used with a length of time.
Since is used with a specific point in the past.
for: ten minutes, one hour, two days, a week, three years, a long time
since: 10 o’clock, Friday, November, 2013, Easter
I’ve lived here since 2012.
I’ve worked for this company for20 years.
We haven’t seen her for ages.
She hasn’t been back to the UK since 2009.
Have you known Sasha since last year?
Have you lived here for more than two years?
How long have you known him?
Have you known Sasha a long time?
Take note: present simple and present continuous
We cannot use the present simple or present continuous with for and since.
WRONG: I know him for ten years.
CORRECT: I’ve known him for ten years.
WRONG: I’m living here since 2002.
CORRECT: I’ve lived here since 2002.
Take note: present perfect / present perfect continuous
With verbs like work and live, which can describe permanent or temporary situations, we usually use the present perfect + ‘for’ / ‘since’ for a long period of time. For a short period, we use the present perfect continuous.
I’ve worked for this company for 20 years. (present perfect)
I’ve been working here for a week. (present perfect continuous)
Take note: present perfect / past simple
If a situation is finished, we use the past simple + ‘for’, not the present perfect:
I worked for that company for 20 years and then I retired.
In informal writing and in speech, we often use a contraction with the auxiliary verb.
I’ve lived in Amsterdam for twelve years.
When you listen to someone using a sentence with for +a period of time, listen carefully to the verb. It is sometimes difficult to hear the difference between, for example, I’ve lived in New York for five years and I lived in New York for five years, but it makes a big difference in meaning. It tells us whether the speaker still lives there or not.
Source: BBC learning English