The document provides advice on staying healthy and contains two sample letters. The first letter is about a person named Yousra who has an unspecified illness making her feel bad. The second letter is about Souleimane, who feels bad and wants advice. The document instructs the reader to write a letter providing health advice to two individuals - Tom, who is sick with a fever and tiredness, and Amy, a 20-year-old who weighs 85kg and has high cholesterol from eating fast food.