"She has a million turtles."
Translation:Zij heeft een miljoen schildpadden.
I guess this is where Duolingo falls short - you keep on getting wrong answers because you don't know the rule that you can leave "een" out for 100 and 100 but not for a million, then go onto the forum to find out from some kind person. It would be nice if the site had some kind of sidebar that mentioned these rules. Or maybe it does and I haven't noticed it.