Founding the concept of homographs,we can differentiate a character phenomenon from a lexical phenomenon,and explain certain phenomena that can t be well explained by borrowing of characters.

Through paying attention to the differences and the relations of folk characters,wrong characters,interchangeable characters and variant forms of the same character,the existing problems of folk characters types are analysed,then the new classification methods are proposed in accordance with the variant forms of the same character types.

In Hui Lin s Yiqie Jing Yin Yi,there are some terminologies such as"the vulgar general character""the customs of the time""the character uses in common " "the vulgar general character" "the unauthorized character"are all belong to folk character.

With the influence of the traditional idea that the standard form of Chinese characters was thought highly, the folk characters in Shuo Wen, the precious Chinese character fossil, was not valued.

In this scripture,there are many common words and common phrases.

From linguistics view, the Dunhuang scriptures of the 85th volume are not only the new materials for studying buddhist scriptures, but also good ones for studying common words and common phrases of Dunhuang documents.