A Encouraging Comment
I always feel encouraged when people who are learning English on Duolingo, talk on the forums.
It encourages me to see that Duolingo has taught them enough to understand a discussion, and then be able to type a comment on their own.
What encourages you about Duolingo?
One thing that encourages me is the community. I like relating to people that have difficulties with a language. It shows that everyone has their own pace with learning, and whether it takes you a few months, or a couple (or many) of years (which is me), we will all eventually master a language with dedication and hard work.