Instruct: Classify Amazon reviews into positive or negative sentiment
Query: The practice tests in this book gave me a good workout.

Principles are taught with practice afterward. There are five complete practice tests provided. There appear to be some errors in the book and the paper is the cheap stuff. This book is consumable if you work all the tests and write essays in it as I did. I took the test last weekend and I felt confident afterward, though I haven't gotten my score yet.