Complex sentence: She later worked as a motivational speaker for a respected international company and has written copy and other material for a number of companies while working for many years as a consultant in telemarketing, sales, marketing and promotion.
Split into simpler sentences: She later worked as a motivational speaker for a respected international company. She has written material for a number of companies, and she has also worked for many years as a consultant in telemarketing, sales, marketing and promotion.