UK:*UK and possibly other pronunciationsUK and possibly other pronunciations/ˈsɪns/US:USA pronunciation: IPA and respellingUSA pronuncation: IPA/sɪns/ ,USA pronunciation: respelling(sins)

WordReference Collins English Usage © 2020
You use since to say that something has been true from a particular time in the past until now.
Exam results have improved since 2001.
I've been wearing glasses since I was three.
Be careful
In sentences like these you use a perfect form with since. Don't say ‘Exam results improved since 2001’ or ‘I am wearing glasses since I was three’.
You can also use since to say how long ago something happened. When you use since like this, use a simple form. For example, instead of saying ‘I last saw him five years ago’, you can say ‘It’s five years since I last saw him'.
It's three months since Kathy left.
It's years since I heard that song.
If you want to say how long something has been true, use for, not ‘since’.
We've been married for seven years.
I've known Adeel for ages.
➜ See for
‘during’ and ‘over’
To say how long something has been happening, use during or over.
A lot of rain has fallen during the past two days.
Things have become worse over the past few months.
➜ See during
➜ See over
‘from ... to’
To say when something began and finished, use from and to.
Mr Ito was headmaster from 1998 to 2007.
Instead of ‘to’, you can use till or until.
The noise continued from nine in the morning till 5 p.m.
Be careful
Don't use ‘since’ and ‘to’. Don't say, for example, ‘He was headmaster since 1998 to 2007’.
used to mean ‘because’
Since can also be used to mean ‘because’.
Aircraft noise is a problem here since we're close to Heathrow Airport.
➜ See because
'since' also found in these entries:

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