The usage limit can vary depending on the credits.
One credit corresponds to one word, and the number of credits required per lesson may differ based on how many words the user speaks.
Assuming that one class lasts 20 minutes, with 2,000 credits as a standard, you can have an average of 6 classes per month. With 10,000 credits, you can have 30 classes per month.
On average, 50 to 100 credits are used per lesson.