The PDF/textbook alone is not enough for retention. You really need the accompanying Workbook to practice writing. The textbook exercises are often too few to fully cement the knowledge.
Need to avoid technical jargon, keep it accessible. Ensure each paragraph transitions smoothly. Start with an engaging opening, then go into the structure, content, features, and wrap up with a recommendation. Make sure it's concise but comprehensive, around 500 words? Active Korean 1.pdf