Given reviews from Amazon, classify those review based on their content into two classes: Negative or Positive.

Ex Input:
My Nomad Jukebox Zen Xtra 40GB only worked for 6 months. I no longer have any sound and the battery doesn't charge. When I called customer service I was given the excuse that it wasn't supposed to be used in the gym. As you all know it is marketed to fulfill your portable music needs. If you can't use it in the gym then it is not truly portable. I know many people who use their ipods in the gym and have had no problems for years. This product has fallen far below my expectations. It is not worth the $300, not to mention the fact that it only has a 90 day warranty. Can you trust a product that is only guaranteed to work for 3 months? No.

Ex Output:
Negative


Ex Input:
This video is fine for ballroom dancers, but it has nothing to do with the authentic Argentine Tango. Even ballroom dancing has now a separate category for Argentine Tango. Unfortunately, this video is not that. That's why, I rate it at 1.

Ex Output:
Negative


Ex Input:
I have no background in history and do not pretend to know what I'm talking about in that regard. However, when it comes to grammar, I know what I'm doing - and Howard Zinn, apparently, does not. The chapter of this book that I was given (Chapter 8: On Presidential Liars) was the most horrendously written piece of work I've ever read. Please make note of the fact that I read high school essays frequently; I thought I'd seen it all. Apparently, I was mistaken. According to Mr. Zinn, the American people have been "deceived about" much more than we thought, and should all "deep anguish" over it.

Ex Output:

Negative