You'll have to eventually study outside duolingo if you are serious about learning a language.
I would recommend starting with the duolingo course, completing it, then keeping your tree gold while exploring other learning material. Start with children's books and work your way up. There are also a lot of language exchange chat sites that are good to help you get more comfortable speaking a new language, but you will need a partner to practice with at some point.
Also I've found ReadLang (which I found on HN) to be a very helpful tool for faster learning, and I upload the majority of my ebooks into it.
Thanks. I was curious because I was using Duolingo to help with my (very rusty) Spanish. I could see that it was helping me to recall vocabulary (and some grammar points) but I didn't see how it would help me improve my listening.
Reading your comment, I thought you had achieved near-fluency in Dutch with just Duolingo, and thought perhaps there was some functionality I had missed!
Thanks for the pointer to ReadLang. The click-to-translate and immediate ability to add to a flashcard list are similar to the features I used most in Pleco (dictionary on steroids) when I first started seriously studying Chinese.
I would recommend starting with the duolingo course, completing it, then keeping your tree gold while exploring other learning material. Start with children's books and work your way up. There are also a lot of language exchange chat sites that are good to help you get more comfortable speaking a new language, but you will need a partner to practice with at some point.
Also I've found ReadLang (which I found on HN) to be a very helpful tool for faster learning, and I upload the majority of my ebooks into it.
I hope this helps.