Given reviews from Amazon, classify those review based on their content into two classes: Negative or Positive.
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Question: The title of this video mentions Argentine Tango. Unfortunately, what is being taught on this tape is not authentic Argentine Tango. Not even close. It's ballroom tango. There is a huge difference: in music, style, steps, posture, etc... Don't be fooled by ballroom instructors trying to teach Argentine Tango. The only authentic instruction available on the market comes from authentic Argentine instructors from Buenos Aires.

Answer: Negative


Question: I had almost all of the Jean Auel's books and needed this one to complete my collection. It turned out to be a book club size and I traded it to a friend for the full size version.

Answer: Positive


Question: An AC/DC power converter is a very basic item, so I had little doubt that this sub for the expensive Apple original would be effective, though not stylish. Unfortunately, we have had problems. The Powerbook started delivering electrical shocks and inconsistent charging with this adapter, and they got worse when we moved to a country on 240V. I know that the shock problem comes from the Macally adapter because I have another PB and an original Apple power supply, so can do all combinatorial tests. I like Macally and have several of their other products. I probably just got a bum unit but unfortunately cannot deliver a positive review based on previous experience with the company.

Answer:
Negative