I have been trying to learn spanish for many years. I have a very large vocabulary in spanish, but still can't seem to communicate like a native speaker. There are many subtle nuances to language that are very difficult to pick up on, unless you immerse yourself in the language. Since immersing myself in the spoken language (i.e. moving to a completely spanish speaking environment) is impracticle for me, The next best thing is to read books in spanish. I chose the Harry Potter books because they are on a teen level, thus they are not too simple, and not too difficult. It is a good way to perfect a second language.