Final answer:
The Great Vowel Shift happened during the transition from Middle English (1150-1500) to Early Modern English (1500-1690), significantly altering the English language's vowel pronunciation.
Step-by-step explanation:
The Great Vowel Shift occurred during the transition from Middle English to Early Modern English. This period extends from the late 15th century to the mid-to-late 17th century.
The Great Vowel Shift was a major change in the pronunciation of the English language that greatly affected the phonetic characteristics of the vowels. An example of Middle English can be seen in Geoffrey Chaucer's The Canterbury Tales, where the spelling and pronunciation of words were significantly different from modern English.
The Great Vowel Shift occurred in the Period of Middle English, which lasted from 1150 to 1500. During this period, there was a significant change in the pronunciation of English vowels.
The long vowels underwent a shift in their pronunciation, resulting in the modern vowel sounds we have today.