Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Worst written and most confusing text book ever

I find this book very confusing, I am a student starting my 2nd year of radiology and this is the first time this book has been used by my college, and hopefully in the future they will find a better book. One of my assignments for class is to define all the key terms at the beginning of each chapter, and they are a joke. Starting in chapter 3 there are 2 key terms Dose equivalent and Equivalent dose you look up the definition for dose equivalent and after reading and defining the term it says, dose equivalent is now called equivalent dose. I think this is very confusing. I have seen several things like this already in this book and have only made it to chapter 3, I will be crazy by the time I get through this book and feel for anyone else that has to use this book.