100 Golden Grammar Rules by Michal Swam

 

 It is astonishing how much enjoyment one can get out of a language that one understands imperfectly. 

— Basil Lanneau Gildersleeve

12. Use For with a period of time; Use since with the beginning of period.

- for the last two hours = since nine o'clock 
- for three days = since Saturday 
- for five years = since I left school

I have been learning English for five years. NOT I have been learning English since three years.

We have been waiting for ages, since 8 o'clock .