Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Practical, enjoyable and worth it.

This was well worth the investment. While based in simple principles stated succinctly it allows you to motivate yourself in the car on the way to work, at night before bed... anywhere ... any time. That repition and ease of listening starts making the "100 ways to motivate yourself" become ingrained at you start living them without making a consciencious effort.