I Love Duolingo..
Thank you to all the team at Duolingo, and the users, that make this an amazing and second to none site!! It has helped and will continue to help me so much!!
Good to know. I am sure this is the idea that Luis von Ahn and Severin Hacker wanted learners to feel when they started this company. Quite a challenge too. A interesting podcast on NPR talks about this company's starup. https://www.npr.org/2020/05/22/860884062/recaptcha-and-duolingo-luis-von-ahn They don't start talking about Duo until the end, but still, very intriguing.