Abstract:
From my observation of Nakhon Si Thammarat dialect nowadays, words spelled with long high vowel (i:, ɨ:, u:) are unusually pronounced as the corresponding words in Bangkok Thai. Even though there have been studies on this phenomenon, no explanation of such variation has been provided. Therefore, this study aims to examine the variation of long high vowels (i:, ɨ:, u:) in Nakhon Si Thammarat dialect in order to analyze their variants and their relationship with phonological environments and social factors. It is hypothesized that each of the long high vowels (i:, ɨ:, u:) has two variants: the standard one [i:, ɨ:, u:] and the vernacular one [e:, ə:, o:], and that their occurrences are influenced by phonological environments; i.e., tones, initial consonants and final consonants, and the speakers age, gender and style. Data was collected from 80 informants in Tambon Suan Khan, Change Klang District, Nakhon Si Thammarat Province. They were 12-80 years old and divided into 40 males and 40 females. Formal style data was obtained by asking them questions so that they would answer them by using 36 words in a list and informal style data was elicited by having them talk on four topics about everyday life. The results of the analysis show that each of the long high vowels (i:, ɨ:, u:) has two variants: standard and vernacular. The standard variants occur more frequently than vernacular ones. Concerning the phonological environments, the results show that the standard variants [i:, ɨ:, u:] appear in all the environments and are used more frequently than the vernacular ones in almost all of the environments. The syllable structures that according to Brown and Diller require [e:, ə:, o:] turn out to contain both [i:, ɨ:, u:] and [e:, ə:, o:]. It is also found that there is a significant correlation between social factors and the use of long high vowels. Female speakers use the standard variants more frequently than male. Young speakers are found to use the standard variants more frequently than older speakers. Also, the standard variants are used more in formal style than in informal style. These results confirm the hypotheses of this study.