The system of Sino-Vietnamese elements and Chinese characters have a relationship which has developed over the two thousand years since the beginning of the Christian era. This relationship can be divided into three phases based on the status and influencing level of Chinese characters in Vietnam including: from the prehistory to the tenth century, from the eleventh century to the beginning of the twentieth century, and from the early twentieth century to the present. In the first phase, the Sino-Vietnamese element system was formed. In the second phase, it was developed together with Chinese characters in Vietnam. In the third phase, it has been developed together with Vietnamese script, moving away from Chinese characters. This paper surveys this relationship based on 500 Sino-Vietnamese elements currently existing in Vietnamese. In this relationship, the Sino-Vietnamese elements borrow the meaning of the Chinese characters including the wholly borrowing ones (accounting for 3%）and the partially borrowing ones (accounting for 97%). The Sino-Vietnamese elements borrowing the original meaning of Chinese characters account for 57% while those do not account for 43%. The independently used Sino-Vietnamese elements account for 18%, and the non-independently used account for 82%. Some elements which create new meanings account for 8% whereas those which do not account for 92%. With such borrowing and creating characteristics, the system of Sino-Vietnamese elements has evolved and developed in terms of meaning. The ability to create words of the Sino-Vietnamese element system is created by turning morphemes into one-syllable words, combining morphemes, and repeating morpheme. The repeating method has little effect on the foreign elements. The method of turning morphemes into one-syllable words forms a number of word classes, accounting for 18%. The combining method is formed when combining Sino-Vietnamese elements together or combining Sino-Vietnamese elements and non-Sino-Vietnamese elements. This method forms precedent or unprecedented words in Chinese. The characteristics of creating the meaning and the ability to form words of the Sino-Vietnamese element system have proved the vitality, adaptability, and strong development of the Sino-Vietnamese element system as a word forming element system in Vietnamese. In the context of written language development in Vietnam today, the previous parallel relationship between the system of Sino-Vietnamese elements and Chinese characters has been severely damaged. Most Vietnamese users no longer have a clear understanding of the relationship and cannot trace the origin of Sino-Vietnamese elements. Therefore, reconstructing the relationship, studying its value, and creating search tools have become critical. This contributes to helping Vietnamese users understand more deeply and use more accurately the Sino-Vietnamese element system in Vietnamese.

Sino-Vietnamese pronunciations are the way Vietnamese people read Chinese characters. Going through the process of formation and development, they have become an important part of the Vietnamese language. In the field of literature, Sino-Vietnamese sounds are closely related to Tang poetry in China and Tang poetry in Vietnam. Tang poetry is a Chinese literary achievement consisting of systems of authors and works with strong influences on Sinosphere countries in medieval time such as Vietnam, Japan, and Korea. In Vietnam, Tang poems are read by Sino-Vietnamese pronunciations, which ensure tonal harmony. Scholars in China, Vietnam, and other countries have studied Tang poetry in terms of phases, authors, styles, and ideologies. However, there has been no attempt to investigate the characteristics and functions of Sino-Vietnamese pronunciations in Tang poetry. In this paper, we study the characteristics and functions of Sino-Vietnamese pronunciations in Tang poetry in China and Vietnam based on the comparison of similarities and differences of reading Tang poems by Sino-Vietnamese pronunciations and by contemporary Chinese by means of surveying 133 poems in Three hundred Tang poems. Comparative data on the ability to keep Tang poetry’s same tone rules and Tang poetry’s rules of Sino-Vietnamese pronunciations and contemporary Chinese show that both types of reading can either remain or break the rules of this poetry type, but their proportions are different. 54% of poems by Sino-Vietnamese pronunciations keep Tang poetry’s same tone rules and Tang poetry’s rules while the rate of poems by contemporary Chinese reading is 34%. The number of poems in which Sino-Vietnamese pronunciations can keep the rules while contemporary Chinese cannot is 28 (accounting for 21%). The number of poems in which contemporary Chinese can keep the rules while Sino-Vietnamese pronunciations cannot is 1 (accounting for 1%). The survey results show the remarkable advantages of Sino-Vietnamese pronunciations regarding the ability to keep Tang poetry’s same tone rules and Tang poetry’s rules compared to the contemporary language used by Chinese people. This is attributed to the fact that Sino-Vietnamese pronunciations are close to the sounds of Tang poetry and still preserve the tone patterns. With such a characteristic, in the process of cultural adaptation, Vietnamese people use Sino-Vietnamese pronunciations to compose, translate, as well as appreciate and study Tang poems. There were thousands of authors, and there were poetry collections of thousands of Tang poems written in Sino-Chinese in medieval time. The similarities and differences between Sino-Vietnamese pronunciations and contemporary Chinese in Tang poems prove cultural adaptation among nations, contributing to preserving the diverse beauty of valuable literary works of humankind.

Chinese characters are materials of Chinese poems in Vietnam, including three main factors: configuration, sound, and meaning. Among those factors, generally configuration and meaning were borrowed from the Chinese while the Sino-Vietnamese sound has been developed since the linguistic acculturation of Vietnamese to Chinese language. Chinese configuration with cultural insides shown in non-numerical configuration has contributed hidden values to the works. Ideograph characteristic of this writing system generates emblems with deep cultural dimension. Analyzing Chinese character configuration is to get more understanding on the meaning of the word and to understand different hidden meanings of the word. The expressions shown on character configuration become a tightly connected system, increasing expressional value for the work and creating artistic messages. Sino-Vietnamese sound of the Chinese works in Vietnam still preserves the characteristics of similarity, prosody, and rules of ancient poetry. Comparing Sino-Vietnamese sound and Vernacular Chinese sound, we will see that, in many cases, Sino-Vietnamese sound (related to audio-track) preserves the characteristics of similarity, prosody, and rules of ancient poetry but the Vernacular Chinese sound may not. Rules on tone bring up beautiful poetry feelings of an era with distinct features. In understanding the meaning of non-numerical scripts, we care about the synonyms with slightly different meanings, which create specific values for poetry works. Chinese words with the same radical can be connected as far as their meanings go, transferring values that readers can discover based on those connections. Multiple meaning words directly contribute to the multi layers of the different layer of meaning in literature works. In general, readers need to be aware of configuration, sound, and meaning of Chinese characters in order to understand the values of Chinese poems in Vietnam.