I can't speak English fluently yet, but I'm doing my best to become better at speaking !
I'm not good at English yet, but I'm studying hard to become fluent!
どちらでもいいです！
fluent = ペラペラ
to do your best = 一生懸命頑張る
to become better at speaking = 話せるようになる
to be good at something = 上手
yet = まだ
to study hard = 一生懸命勉強する
to become fluent = ペラペラになる
役に立てば嬉しいです！
ロシア連邦 
