Improving English
It is so interesting how fast one's English can be improved. All you need to do is practice English. So, that's the only thing I'm devoting my time to. And there is nothing to object to about how fast I'm progressing. I really want to speak like a native English speaker, and it's not so easy, of course. To achieve this aim I should use English as often as possible. The funny thing is that I understand English perfectly and speak it near-fluently, but sometimes I'm confused about which words are appropriate. I want my speech to be natural for native English speakers. So, I hope my use of English will grow more natural.

Lots of places where it sounds odd, but it's all perfectly understandable, which is good. It rambles on a bit, too, but I assume that's because you just wanted to get as many words out as possible.