Introduction: It is one of the major languages ​​of the world and is the international language nowadays. English language is the language which has faced many changes which affect several things. For example, some changes occur in the writing system, phonological system, and other changes over several centuries. The English language consists of four stages: Old English, Middle English, Modern English, and Early Modern English. In every era, there is an attachment of the languages ​​of other tribes to the English language. As an example, Germanic tribes that settled in Britain and had an impact on the Old English language are the Angles, Saxons and Jutes. Similarly, the effects of tribes lead to many changes in the vowel system, called the Great Vowel Shift. In this article I will discuss the Great Vowel Shift and the process of this enormous change. Vowel Shift: The Great Vowel Shift occurred in Modern English between 1500 and 1800, resulting in some changes from Middle English to Modern English. Otto Jespersen is a Danish linguist and discoverer of the Great Vowel Shift. He was the first person to study the vowel system and the great vowel change. Additionally, this period is called the Great Vowel Shift because of the enormous change that occurred in the vowel system at this time. In addition, changes appear in pronunciation between the 15th and 18th centuries. Additionally, The Great Vowel Shift constitutes a huge change in the sound system and affects the long vowel of English from the 15th to the 18th centuries. The meaning of the Great Vowel Shift is “a racial change in pronunciation during the 15th century, as a result of which the sound of long vowels began to be made higher and more forward in the mouth. The short round sounds have remained largely unchanged.” . middle of paper ......fi:f) five Ĩ(mi:d) (med:ₔ)meed Ē(go:t) (gᵓ:to) goat Ā(ru:t) (ro:to) root Ō(daun) (du:n)down ŪFrom the table above, there is an obvious difference between Chaucer and Shakespeare in the way they write. Additionally, the differences in the way of production, all of this is a result of the great vowel shift that occurred in the 16th century. Conclusion: To summarize, the big vowel is one of the huge changes in the English language. The Great Vowel Shift changes the way words are produced from Middle English to Modern English. Additionally, the Great Vowel Shift has an effect on English linguistics and literature. For example, the differences between Chaucer and Shakespeare in their writing and word production. Finally, I think The Great Vowel Shift makes the English language modern after the affection the language has faced. .