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

Example Input: I personally enjoyed ever word of this particular work. Many other reviewers have gone into the plot, etc. so I will not do so here to any depth. This is one of those works of SiFi that will appeal to certain taste, while others may find it not to their liking. There is a great deal of politics (almost Pre WWI European) involved in the story line. As the story covers (all books included) over one thousand years, there are many, many characters to track and keep track of. This is indeed a series of short stories, all linked. I personally enjoy this sort of thing but can see where some might not. That being said, it, the book, can certainly be regarded as a classic in this particular genre and certainly should be read by any student of such. You certainly cannot fault the author's story telling ability and imagination. I enjoyed this one a lot and do highly recommend it.
Example Output: Positive

Example Input: Received this in great time- I have no problem with the seller:-)BUT! The inside of the case lists all types of materials this can cut including metals, which is what I got it for.One punch through soft 26ga copper sheet and the edges of the punch bent & in some areas, flaked off. The second disk I cut did it in completely. I had to file all of the edges and it probably would have been easier to cut the sheet with shears.So, not for metals.However, I can see it would be great for leather, paper & plastics.To me it was worth the money spent on the chance that it would actually cut metal disks.
Example Output: Negative

Example Input: I used this product 19 years ago after my pregancy while working out and getting back to shape. I had a slimmer waist within weeks. You tend to sweat and lose inches having this on. It is a bit uncomfortable at first and it takes getting used to, but I would wear it only while working out. Otherwise, I would take it off.19 years later, after having my second child, I was looking for the same waist cincher which I just received and began working out with it. I am a firm believer this will bring my waist to where I was prior being pregnant with my workouts. It is well made and sturdy. The metal hooks never pinch nor they unhook while doing exercising. I recommend this product.
Example Output:
Positive