Given reviews from Amazon, classify those review based on their content into two classes: Negative or Positive.
Example: I've read this book with much expectation, it was very boring all through out the book
Example solution: Negative
Example explanation: Review writer does not like the book because it was boring, therefore it is a negative review.

Problem: I bought the Zen Xtra 40Gb yesterday, taking it back today. The sound is awful. The volume range goes up to a 25, and even with the EAX or whatever it's called on, it's barely audible. I don't know if it's the jack gone like you all say or if this is just designed for easy listening. No good for loud music. Prepare to listen to background noise, not your music. This thing sucks. Don't buy it.
Solution: Negative