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:
I was so excited when I received this air bed, but after sleeping on it on the first night, things changed. Every single night I had to put more air in it in order to keep it firm. There were no leaks that I could hear, but it was a pain to keep putting air in it every night. If this does not bother you, the bed itself is extrmeley comfortable.Intex Pillow Rest Queen Airbed with Built-in Electric Pump
Answer:
Negative