Adverb and objects bug
Theres a a bug with Spanish Adverbs and Objects that wont let me level up to gold.
I had the same problem on my tree with a different lesson. I would finish the lesson, but it wouldn't change to gold. The only thing I figured out was that I was completing the lesson too fast (it contained words I knew well) and didn't review all the words. I think I did the lesson 3 times and then it changed to gold.