(1) Polymorphism in elements is called allotropy.

(2) To compare the words of allotropy and "Dictionary" have been found , make it as a valuable example of lexicography.

(3) Briefly discuss on the value of Words allotropy, point out the deficiencies of the full text , and can go further into the area.

(4) Words of allotropy in Tai Ping Jing are in two categories: one is AB and BA used at once, the other is AB in modern Chinese but in Tai Ping Jing only BA found.

(5) Finally, it explains the reasons of appearance about allotropy from the Chinese history.

(6) The second chapter, study the eight groups appear allotropy word in "Yi Jian Zhi" in Longitudinal.

(7) The third chapter to research on voice, vocabulary, grammar, rhetoric, culture, psychology and language habits from various angles to explore the reason of allotropy in " Yi Jian Zhi ".

(8) A structurally differentiated form of an element that exhibits allotropy.