Instruct: Classify Amazon reviews into positive or negative sentiment
Query: The River of Doubt, a Review

In this book, you learn a lot about two unknown facts, the life of Theodore Roosevelt after his presidential career, and the River of Doubt, later named the Roosevelt River in the western Amazon. Having lived in the Territory and State of Rondnia, near the source of the Roosevelt and Ji-Paraná rivers, I was particularly interested. However, I would have liked to read about Roosevelt's travels from the mouth of the River of Doubt at the Arapuan river and then to the Madeira, still a long way from "civilization" to Manaus.