Since, for, from

Since
Since expresses duration up to the present.

When we use since, we are saying that something began in the past, but is unfinished.

I have lived in this house since 1997.
(= 'I moved here in 1997 and I still live here.')

We’ve been married since last June.
(= 'We got married last June and we’re still married.')

I've known him since we were at school.
(= 'I knew him at school and I still know him.')
We use the present perfect simple or present perfect continuous with since.

I have had this car since last April.
Mary has been working here since 2003.
We can use the past perfect tense with since to express duration from a point in the past.

It was 1974 and he had been living in London since 1964.
Since vs. for
Since and for both express duration up to a point in the present, but we use them differently.
We use since + the starting point of the activity.

We have lived in this house since we got married.
I've been waiting here since 9 o'clock.
We use for + a time period:

We have lived in this house for thirty years.
I've been waiting here for three hours.
Since vs. from
We use since and from to express duration. Both tell us the starting point of an activity.
Since expresses duration of an unfinished action, up to a point in the present.

I've been here since 8 o'clock this morning so I'm going home now.
I've been here from 8 o'clock this morning.
We use from in other cases:

I will be here from 8 o'clock tomorrow.
I will be here since 8 o'clock tomorrow.

The shop is open from 9 a.m on Saturdays.
The shop is open since 9 a.m on Saturdays.
We say from . . . to or from . . . till / until.

He works from 8 to 5.
From the 1920s until his death, Picasso lived in France.

Practise this grammar

Intermediate grammar exercise: Since, for, from