TelegramBot - teacher of Polish language

Telegram-Bot is a teacher of foreign languages (LennyEnglishBot).
The main functionality:
1 . Learning new words (limit by subscription)
2nd Automatic reminder of the need to repeat new words
Three Repeat the words that have been learned before (subscribe limit)
4 . Periodic notification of the need to repeat the words
and 5. Notification of paid subscription to reach the word limit
6 . Possibility of sending messages paid, free and to all subscribers
Settings for each user (language of the menu, language of translation, word output mode, choice of them, etc.)