This paper focuses on the disyllables formed by the consecutive use of ancient and current synonyms in ‘Chunguijigeon(忠義直言)’. The newfound book ‘Chunguijigeon’ was used as a Chinese textbook in the early days of the Joseon Dynasty. This book has great historical significance that one can understand the Chinese vocabulary of the time by studying the words used in this book. The words in this book reflect the distinct characteristics of Modern Chinese, especially the phenomena occurred during the substitution of colloquial and literary language. For instance, large numbers of disyllable such as ‘Jiedou(皆都)․Douquan(都全)’, ‘Fangcai(方纔)/Fangcai(方才), Caifang(纔方)/Caifang(才方)’, ‘Jiubian(就 便)’, ‘Jiangba(將把)’, ‘Zicong(自從)’ and ‘Bianxiang(邊廂)’ have been discovered. The monosyllables that compose those words are used as synonyms simultaneously in the literature, though created in different period with the disyllables. Examples of those monosyllables include “‘Jie (皆)․Dou(都)․Quan(全)’, ‘Fang(方)․Cai(纔)․Cai(才)’, ‘Jiu(就)․bian(便)’, ‘Jiang(將)․Ba(把)’, ‘Zi(自)․Cong(從)’, ‘Bian(邊)․Xiang(廂)’. The disyllables which was formed by the consecutive use of ancient¤t/new&old synonyms have great historical significance, in the sense that they show the conflation of language of the transition period caused by contacts of language.