Geoffrey Chaucer's contribution to English literature is extremely important.
He was the first English writer to write in the vernacular. Previously, Latin was the language used by writers. This enabled writers from various countries to share what they had written since Latin was the language used by scholars.
In his unfinished work, The Canterbury Tales, Chaucer gives us a wonderful picture of the medieval world. His pilgrims come from all classes of medieval society from the Knight and his Squire to the various members of the clergy, to the merchants and finally the average working man.
Through his descriptions in the "Prologue" and through the stories they tell, he reveals a lot about the people in this society. He gives us the good, the bad and the ugly.
Chaucer's Canterbury Tales is mirror that reflects English society in the late Middle Ages.
Chaucer is sometimes referred to as the "father of English poetry." Part of the reason for this is that he was writing in Middle English and his work marks a major transition between the scanty remnants we have of Anglo-Saxon epic and early religious poetry and the development of a modern English poetic corpus.
Perhaps Chaucer's most important achievement was his role in the formation of the English vernacular as a tool for poetry. Most of the English poets in his period wrote in French or Latin for court or ecclesiastical audiences. In contrast, Chaucer wrote in English, which was accessible to a wider audience. His subject matter, too, while it included courtly romance, also often dealt with the ordinary lives of the bourgeois. In The Canterbury Tales, for example, among his pilgrims are many commoners, who are described in an unusually realistic manner.
Chaucer is also a key figure in the development and regularization of iambic pentameter as the standard meter for English poetry. He was especially important for using accentual syllabic verse that blended the strong stress tradition of Old English with French accentual meter.
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There is the great contribution of novel to English literature:
01. Ground for novel
02.Ground for short stories
03. Ground for drama
04. Narrative form
06 Chaucerian stanza
07. Mirror of the age
08. Modern Language
09. The Prologue as the good work.