He iambicpentameter couplet. His most famous work CanterburyTales, socialsignificance aspects:First, true-to-lifepicture 14thcentury; Second, humanistliterary work, praisesmen’s energy, quick wit, intellect thusforeshowed EnglishRenaissance; last,taking risingbourgeoisie, affirmsmen degeneration(堕落)of Chaucer’sposition contributions.Chaucer has got titles:He’s Englishpoetry; Englishfiction; Englishrealistic literature somecritics). firsts:He firstpoet who broke through OldEnglish device, alliteration, newrhyming scheme rhyme royal—ababbcc; Second, he firstone who introduced from French heroiccouplet English;third, firstgreat poet who wrote currentEnglish language, London;fourth, he Englishhumanist literature Englishrenaissance.