This document discusses English consonants and vowel pronunciation in three sections: 1. Stress-timed open syllables contain a vowel letter followed by a consonant letter and silent e. The vowel is pronounced as its base sound. 2. Stress-timed closed syllables contain a vowel letter followed by one or two consonant letters without a silent e. The vowel is pronounced as its short sound. 3. Unstress syllables have reduced vowel sounds compared to stress-timed syllables. The document provides examples of vowel pronunciation in different syllable types.