I'm going to try every tree today.
I haven't tried some languages so I'm going to get to level two in every one so I have a lot of flags, wish me luck Duo! I'd just like to say thanks to the staff of all these new languages, Korean, Czech, Japanese, and even High Valyrian, this is the best language learning app for one major reason, the price! Twenty years ago, language learning was limited to only people with the money to fund their studies, but the digital age is changing that and Duolingo is at the forefront of free language learning. Duo is still in it's fledgling days but I know that it will grow into something even greater! I am also so very excited to hear that Mandarin will be coming soon as I want to study it more than any other language not yet here (Icelandic is a close second because I find the island fascinating)
Alright! I tried every one except for High Valyrian (Which I will try when I am done with this post) The hardest at first glance, for me a native English speaker, is Turkish, Hungarian, Hebrew, and the slavic languages (espescially Polish which seems insane) Vietnamese and to a lesser extent, Irish Gaelic. I found out that I like Romanian, & Welsh which i did not realize before and am now considering taking one on. As far as the romance family goes, French seems to be the hardest, and in Germanic I found the Danish spelling to be really weird. This is also the first time I ever got more than 1000 EXP, which is a huge milestone, as my old record was 300 and something. Thanks for your comments, and happy language learning!