Learning two or more languages at the same time
I'm currently learning just German, but I've been thinking about picking up Italian as well. My question is, if I did that would I have to earn XP in both of those languages to keep the streak going?
Not currently; I'm studying three languages and the XPs are just additive.
Just to add to this, the phone and ipad apps keep language specific streaks (unless this has changed.) The website works with a global streak, so XP from any course can go towards your streak. So, you might end up with a different streak on your phone than you have on the website. :)