Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Review of the book City of Ember

This was an excellent book. It shows you what could happen to the world someday. We all may have to live in a city that is lit by lightbulbs because we may have destroyed our true world.In this book Lina is a 12 year old girl who happens to come uppon an very old piece of paper which seemed to have instructions on it. But to bad for her her little sister Poppy found the paper first and chewed big chuks out of it. Lina and her friend Doon must find out what the instructions say so they can save there city. Or maybe even find a way out.