I have been using Duolingo for a long time. I really do not like that fact that there is no way to give the company feedback. I believe they started out with good intentions, but now just want to make money. They have recently removed many features that long time learners like myself enjoyed - such as the vocabulary list - and there is literally no way to ask them a polite question as to why and whether they might consider replacing it. Also, they have added a lot of new content that are many errors - I am not the only one who has found these - and they have been very slow to correct the mistakes. Finally, they have removed defining what each word or sentence means in English! This is crazy. It doesn't matter if you got it "right" if you don't know what it means. Looking up each word is useless, as sometimes the whole is greater than the parts and the meaning is not obvious.I think they have gone down the rabbit hole of profits...and the product will get worse and worse. Use the free version if you want to, but I don't recommend paying for this product.