I 've studied English 3 years in the Middle School, 3 years in the High School, 4 years in the University. But I still lack practice because I think that production "performance" is more important than reception "competence". You know that studies in the middle and high schools aren't "very high level". We study the basic elements of the language and we usually do not assimilate them all.

I would be pleased if you could correct my writing and help me out with the most used structures to make my English seem the outcome of a professional if not a native speaker and not only a learner.