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

Let me give you an example: I've read this book with much expectation, it was very boring all through out the book
The answer to this example can be: Negative
Here is why: Review writer does not like the book because it was boring, therefore it is a negative review.

OK. solve this:
It was a little big for me, but it worked really well until about two weeks ago. And then it just died. Mind you, this is two months after I bought it. I switched the batteries, made sure the ones I put in were working, but I suppose the motor died. I never even used it in water. I don't know about most people, but for $30, you'd think you'd get more than two months out of a vibrator.
Answer:
Negative