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:
Itten's analysis and application of color is thoughtful and scientific. As a practicing art director, I have successfully used the theories and methods explained in "Elements of Color" for over twenty years. I also teach them to my design classes. Whether you use a paintbrush or a mouse, his "seven color contrasts" will prove invaluable.
Answer:
Positive