1. Introduction

Overlap is a common morphological operation in world languages, with syntactic and semantic functions. The overlap of different languages exhibits different characteristics in phonological patterns, which has theoretical value for morphological, phonological, and typological research. This article compares the noun overlap structures in two tonal languages, Chinese and Bantu, from a cross linguistic perspective. Chinese is an isolated language with limited inflectional forms; Bantu language is a agglutinative language with rich inflectional variations. There are commonalities in phonological types between the two languages, such as tonal languages and simple syllable structures. The simple syllable structure of tonal language is often accompanied by rich non connected morphological processes, such as pitch change, tone change, and overlap. The interaction between morphology and phonology in Bantu language has significant value for the development of modern phonological theory. The study of Chinese dialects has provided detailed descriptions of the patterns, functions, and phonological characteristics of overlapping structures, but there is relatively little comparative research on typology across dialects and language families. This study aims to clarify the functional and phonological characteristics of noun overlap in Chinese dialects and Bantu languages, and analyze the commonalities and differences of overlap structures in these two types of tonal languages.

2. The productivity and function of noun overlap

Noun overlap has different functions and phonetic structural characteristics in Chinese and Bantu languages. In Chinese, noun overlap mainly refers to being small, while in Bantu language, noun overlap refers to being large and expressing typical functions more commonly. The overlapping of Chinese nouns also has the function of nominalization, and there is a similar phenomenon in Bantu language, but with lower frequency and productivity. In Bantu language, noun overlap can form plural forms, but this phenomenon has not been found in Chinese. Chinese noun reduplication mainly involves three categories of actual words: name, action, and form. Verb reduplication has the highest productivity, while noun reduplication depends on the specific language. Adjective reduplication has a higher productivity in Chinese dialects and a lower productivity in Bantu languages. The noun system in Bantu language is classified into different categories based on semantic and grammatical features, indicated by prefixes, with a typical structure of "category prefix+stem". Noun overlap also varies in expressing small amounts, disgust, or disapproval attitudes.

3. Structural characteristics of duplex

This chapter compares and analyzes the structural characteristics of duplexes in noun overlap between Chinese and Bantu languages, including the position and phonological structure of duplexes. In the overlapping structure of Chinese nouns, the compound can be located on the left or right side of the base form, with the postposition form being more common. For example, the noun overlap in Xining dialect is postpositional, and the segmental content of the compound base is duplicated, with only 44 and 53 tones; The noun overlap in Qingxu dialect is a prepositional form, and the compound vowel is unified as [əʔ], replicating the tone and initial consonant of the base form. There are also two types of noun overlap in Bantu language: prepositional and postpositive, with postpositive being more common, such as in Lusoga and Kinan German.

4. Autonomy in tone replication

Explored the autonomy of tone duplication in noun overlap between Chinese and Bantu languages. Tone has independence in tonal language and can function without relying on segmental components. The segmental components and tone forms of morphemes can be replicated separately, and there are four possible replication modes: 1) segmental and tone replication simultaneously; 2) Partial segmental and tonal duplication; 3) Only segmental duplication; 4) Only tone reproduction. The first three modes have examples in both Chinese and Bantu languages, while the fourth mode has not been reported yet. Three types of duplication situations were specifically analyzed: 1) the segments and tones of the basic form were duplicated simultaneously, such as the overlap of nouns in Pingyao dialect and Ensong language; 2) Partial segments and tones of the basic form are replicated, such as overlapping nouns in the Qingxu dialect; 3) Only the basic sound segments are copied, such as overlapping nouns in Mandarin and some Bantu languages. These analyses reveal the diversity and complexity of tone replication in different languages.

5. Conclusion

The theoretical value of overlapping structures in morphology, phonology, and cross linguistic typology was emphasized, and their similarities and differences were revealed by comparing the noun overlapping structures of Chinese and Bantu languages. Noun reduplication has both referential and nominalization functions in both languages, but Bantu language emphasizes greater referent and expression typicality. In terms of phonological structure, both languages tend to have a complete overlap of postpositional forms, but there is also a partial overlap phenomenon, reflecting the requirement for morpheme prosodic structure. The partial overlap of Bantu language is limited by the disyllabic structure, while monosyllabic is a commonly used structure in Chinese dialects, and the types of syllables are more diverse. As a tonal language, the overlap of nouns between two languages demonstrates autonomy in tone duplication, which can be synchronized with segmental overlap or achieved through fixed tones or default assignment. The origin of compound tones and their relationship with tone systems deserve further exploration, which has theoretical significance for the typological comparative study of cross tone languages.