The Influence Of Stress Shift On Vowel Change In British English Words: An Experimental Analysis

Compared with Chinese - a syllable-timed language, English is a stress-timed language. As the suprasegmental feature of syllable, stress, which closely relates to sound-articulation, word-formation and grammar, is one part of linguistic organization and one of the essential factors in phonetics. Stress is defined as the prominence given to certain syllable in a word, to a certain word in a compound word, or certain words in a sentence.Vowels are the very important part in the speech chain, which are indispensable in linguistic organization. The researches on vowels have been the most complicated problem in studying phonetics and phonology. The research in this regard is determined by the characteristics of vowels that vowels are liable to change, because vowels have been undergoing great changes with the passage of time. In fact, English vowels have greatly changed from the Old English, the Middle English to the Present English. Diachronically, the process of vowel development is the course of vowel change. Consequently, vowels tend to be less steady than consonants in English. Why did the vowel change happen? What are the reasons for the change? What are the results of the change?Many linguists and phoneticians have made great contributions to this phenomenon, such as Daniel Jones, A.C.Gimson, J.C.Weils, Leonard Bloomfield, Noam Chomsky, etc. Their researches on phonetics reflect the long historical vowel change from various perspectives, such as the English history, the rules of change, the reason for change, the result of change, the typical change phenomenon, etc. Their theories provide meaningful information for further research on this topic. Based on the previous research by linguists, stress is an important factor among the reasons for change, in the sense that the change of stress or the stress shift has, to some extent, caused vowels to change. Then synchronically, does the stress shift have influence on vowels? If it has, then what are the results of the influence? All these questions remain unsolved, which need to be figured out. And this is what the thesis intends to discuss.As for the connections between vowel and stress, based on the previous achievements by many well-known linguists and phoneticians, there is close relationship between vowels and stress. In a word, stress is always placed on certain syllable with a vowel in it. The stress of English words is determined mainly by the characteristics of vowels. Stressed syllables are heavy, have an unreduced vowel, and can be assigned a tone (lexical or pitch accent). Unstressed syllables are light, have a reduced vowel, and are not assigned a lexical tone or a pitch accent. These theories lay a foundation for developing this topic deeply.This thesis tries to figure out the influence of stress shift on synchronic vowel change in order to illustrate the close relationship between them. A comparative analysis of the sound recording by native speakers by applying the phonetic computer program - Praat, together with a relatively comprehensive survey of the English Pronouncing Dictionary (15^th edition), the classic book of phonetics left by Daniel Jones, will be adopted to reveal that synchronically, whether or not each vowel in English undergoes dramatic sound change when stress shift happens within a word.As the purpose of this thesis is to figure out whether or not the stress shift has influence on vowel change in English words, the English Pronouncing Dictionary (15^th edition) is chosen as the research corpus, because EPD is an authoritative book on British English or Received Pronunciation (abbreviated as RP), which has established the standard for English pronunciation. In fact, there are various stress differences between words pairs such as 'drama-dramatic or 'Canada-Ca'nadian, 'intrigue (n)-in'trigue (v), 'adult (n)-a'dult (n), and so on. So for the purpose of clarity and convenience, we are going to make survey on these word pairs with identical spelling but different pronunciations. However, though the word pairs are pronounced differently, they are comparable. So the result would be acquired by doing comparative analysis on them. Nowadays, the software - Praat, which is written by the Institute of Phonetic Sciences, University of Amsterdam, is more and more widely used in doing the experimental phonetics, including this thesis. Through the acoustic analysis by Praat together with the survey on EPD, this thesis intends to figure out the influence of the stress shift on vowel change and the result of change from the synchronic perspective.To correctly grasp the stress in English words is rather important both for English learners and teachers. The traditional phonetics has made great achievements in studying the English stress, which forms a relatively comprehensive set of theory of stress. But still it is difficult to distinguish which syllable should be stressed in the English word, so the flexibility of stress position brings difficulties in learning the word pronunciation. The mistakes in stress assignment, wrong pronunciation like accentuating the unstressed syllable, lengthening in vowel duration in unstressed syllable and raising the pitch of the unstressed vowel, etc, would result in the obstruction in verbal communication. These mistakes could possibly be avoided by mastering the correct stress pattern of English words, the right pronunciation of words. Therefore, this thesis is going to focus on the relationship between stress shift and vowel change from the synchronic perspective to provide certain meaningful information for English learners and teachers to acquire better English pronunciation.