This document provides an overview of English vowel sounds. It defines a vowel sound as a vibration of the vocal cords without obstruction of airflow from the mouth. It then lists and provides examples of the most common English vowel sounds using IPA symbols. The document further classifies vowels according to several criteria, such as horizontal tongue position (front, back, central), vertical mouth position (high, mid, low), and lip position (round, spread, neutral). It includes a vowel chart and assigns exercises to practice vowel sounds.