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:
[..]Let me warn all potential customers that this book is all about quantity of material instead of quality. While the book does cover such advanced topics as Fourier Analysis and intro to Partial Differential Equations, the book lacks sufficient examples about what is being said (a number of sections have no examples at all).I did find the most well-written sections to be the application of second-order differential equations (applied to spring oscillations etc.) However, as far as getting a bang for your buck, I HIGHLY RECOMMEND Morris Tennenbaum and Harry Polland's Ordinary Differential Equations Dover edition (cheaper, and MUCH MORE effective. Trust me).
Answer:
Negative