This expanded workbook is meant to go hand-in-hand together with "Korean Made Simple: A beginner's guide to learning the Korean language." However, this workbook is optional; "Korean Made Simple" already contains practice sections with answer keys built into every chapter. As such, this workbook is an additional resource for practicing in addition to using "Korean Made Simple."Each chapter's vocabulary, grammar, and more (including the Korean alphabet and sound change rules) are included as practice in this workbook to help you to more quickly and efficiently master what you're learning.Audio files for the book are also available for free download from gobillykorean.com.