How long to pick up Russian in Russia

I arrived in 2004 for two weeks and then again in 2005 for a month. 2006/7/8 two months each of those years.  Since 2010 around 8 months each year.  I knew no Russian at all when I arrive and took some lessons.   I found it very difficult at first (aged 45) even to identify the sounds; however, slowely it has got better and I can now carry on most vital communications in shops etc. and give basic instructions to children in Russian.  I can understand quite well now.   I think I am the stage where I need to study grammar seriously, as I would now benefit from such lessons.

WE have students here who earn very quickly, but they are in their late teens and early 20's.  One fifteen year old American studied intensively every day for two months and became quite fluent:  quite incredible.

Keep at it!