Since.

We use since after the the present perfect (have been/ have done) .
Since + the beginning of a period (from past to now).
We have lived in Uzbekistan since 1995.
I have worked on the site Lazizbek.uz since may of may 2015 .
It has been snowing since I arrived.
For.
We use for when we want to describe exact period.
Using: for + a period of time.
example: for 2 days, for 3 years.
Allan worked on this project for 3 years.
Mary has been in journey for week.
Next day we going to Samarkand for four days.
Special for Lazizbek.uz .
Written by Adizbek Ergashev.
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