Instruct: Classify Amazon reviews into positive or negative sentiment
Query: A must for anyone with an interest in martial arts

I've read quite a few books on martial arts, and "Ultimate Jujutsu" is definitely one of the most in-depth and comprehensive that I have read. From the history of Japanese Budo to the principles of technique and practice, this book covers all you need to know about Jujutsu. And, since Jujutsu is fundamentally an art of combat and self-defense, anyone with an interest in self-defense and martial arts will be able to learn a lot from reading this book. Two thumbs up!