Examples of using "улучшился" in a sentence and their english translations:
Your French has improved a lot.
Tom's French has improved significantly.
Your English has improved considerably.
Has Tom's French improved?
Your French has improved a lot.
I think your English has improved a lot.
To my surprise, since Tatoeba has been back up, nobody has made any corrections to my sentences. Either my English has rapidly improved and I now produce good sentences only, which is way doubtful, or the users have simply decided to leave me alone and let me write whatever comes to my mind.