Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Great Book, Both Times

I had read this book when I was in Junior High, and always wanted to read it again as I had enjoyed it so much, and was curious to find out what I had missed due to my age at the time. I took advantage of the opportunity to download the book to my iPad and to read it while I was flying on vacation. I found it to be as riviting and exciting as it was when I was MUCH younger, and found that while there were some nuances I had missed the first time around, I had managed to commit to memory the most important parts of the book. I highly recommend this book to fans of Robert Heinlein, or anyone that likes suspense or mysteries set in the future!