The Battle of Grand Gulf was fought on April 29, 1863, during th: The Great Vowel Shift affected the stressed long vowels of Middle English. It was a chain shift, meaning that each shift triggered a subsequent shift in the vowel system. Mid and open vowels were raised, and close vowels were broken into diphthongs. For example, the word bite was originally pronounced as the word beet is today, and the second vowel in the word about was pronounced as the word boot is today. The Great Vowel Shift explains many irregularities in spelling since English retains many spellings from Middle English, and it also explains why English vowel letters have very different pronunciations from the same letters in other languages.[51][52]