I started learning Chinese 10 years ago, two years before I moved here. I've continued studying at a snail's pace, but have only once had a teacher. Back in Guilin, about 4 years ago I found myself feeling embarrassed at how little i'd progressed and so decided to go to college, which I did for 4 months. It helped me 'really' get started on my reading, which i've since continued to improve upon, but the truth is that for someone who has been studying for ten years (whatever 'that' means) my Chinese is still relatively elementary. If you look at the five levels of English taught in most schools, which are often split into ten books in total, my spoken/listening ability would probably be about level 6/7, my reading would be about 4/5 and my writing would be about 1/2. In my experience though, a student who's completed each level from 1-10, is generally able to speak with the competence of an eight year old child who's been speaking the language all their life - whichever language that may be. You get out of it what you put in, and personally, for the past few years, I rarely put in more than half an hour in a day. Having said that though, my wife does speak to me in Chinese about 70% of the time. I have to remind her to do so constantly, but it is an invaluable aid to my Chinese progression. I only reply in English though as I have a kid who needs to know both languages. Jesus, this whole paragraph is a real yawnfest, I need a coffee.

Just bought a learn Chinese book for 49 yuan next day of arrival.(2005)

no classes ,no teacher.

now I can speak fluent . 

I learned basic chinese without any classes. I had taken one class before it was free. I did learn about the meats on that lesson!