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

Ex Input:
If you need a grammar reference, this may well serve until you find a better one. It might be of greater utility if the tone wasn't vaguely condescending and pedantic, and it eschews the panoply of actual examples in favor of definitions. To wit: the 2nd person singular present perfect conjugation of "to love" results in "If you have been loved..." gives me one (singular) example but not the rationale of when to use this. The density of the text preceding the example conjugations will require your own self-study to master (if you must) the ability to spin off a subjunctive 3rd person plural present tense conjugation.The best recommendation I can offer for this is as a companion for language learners who need a quick reference for English analogs of other-language conjugations, such as when you try to conjugate "falar" and need to know which one to use.--#

Ex Output:
Negative

Ex Input:
I've noticed very little degrading of the sound, if at all, and this is rare in most extensions. The cord is thicker than usual for both the positive and negative polarities - a separate wire for each - and I'm quite pleased with this, will perhaps get another because of its thickness. I now have great headphone sound within a twenty-foot range - just what I was looking for. Even if you don't need 15-feet of cord, I would recommend this over the shorter 10 foot cords where the wiring is about half as thick and not likely to hold up over time...I subject all my electronics to heavy use. Plus, the best extensions for Grado headphones go for $40, and I'm quite satisfied saving over $30 by having this one.

Ex Output:
Positive

Ex Input:
I'm an expected father to be, and I thought this DVD would help me show my caring compassionate side... I was trying to be part of the whole child birthing process. Thing is, this DVD provoked an unearthly rage in my spouse. While watching it Bayles seemed more intent on belittle the viewer and sharing her own life story then furnishing us with information. My spouse secretly thought that this Sheri Bayles was trying to ruin her child's birth. The DVD taught us nothing, 80% of this DVD is about Sheri talking about her own life.. The information she did give is easily obtainable from a free pamphlet. When I told my spouse I paid $[...] for the movie she freaked! [...]

Ex Output:
Negative