Hi there! :)
I am not a native English speaker, and I can't say that I know English very well. Nevertheless, I have quite good knowledge of English grammar, and I can also understand English speech freely. However, I usually have some difficulties expressing my own thoughts in this language.
If you are in the same situation, I hope that we can help each other by talking about different topics and discussing any problems :).
BTW, if you're looking for a tandem partner, I am a Russian and Belarusian native speaker, and can help you in improving your skills in these languages if you wish.