Effects of explicit instruction on Korean EFL learners' development of phrasal and compound stress = 구 강세와 합성어 강세 지도를 통한 한국인 영어학습자의 발음 향상 연구

다국어 초록 (Multilingual Abstract)

This dissertation investigates the phonetic implementation of phrasal and compound stress produced by Korean learners of English and native speakers of English and the effectiveness of pronunciation instruction on L2 pronunciation improvement. The purpose of the study is twofold: (a) to examine the acoustical correlates of phonetic stress in phrasal and compound words respectively produced by Korean learners of English and native speakers, and (b) to assess student progress in the phonetic implementation of English phrasal and compound stress during a seven-week English speaking class with the explicit and implicit pronunciation instruction respectively.
This study is experimental in nature, both classroom-based and laboratory, investigating the effects of different instructional approaches on pronunciation learning. Previous studies on the acoustical correlates used by native speakers in the phonetic implementation of stress have shown that they rely on F0, duration, and intensity in stress production. This study focuses on the use of these three cues by Korean learners of English in stress assignment.
The experimental design involves two homogeneous groups of EFL students enrolled in the language program of Chonnam National University, Korea. Pre- and post- tests on two sets of stimuli were administered to participants in all two groups, and native speakers. One set of stimuli contains the sentences that carry the phrasal and compound words for each pair whereas the other set of stimuli contains the sentences with phrasal words only in the simplest syntactic structure.
This study found that explicit instruction affected learners' pronunciation development on phrasal and compound stress. The results showed that the native speakers of English implement pitch and intensity as reliable cues to distinguish compounds from their phrasal counterpart whereas Korean learners do not exhibit any acoustical differentiation in compounds and phrases in the pretest. In the posttest, on the other hand, the participants in the explicit group performed acoustic cues of stress in distinguishing compound words from phrasal counterparts as native speakers do whereas the participants in the implicit group did not show improvement on implementing the acoustic cues of stress in distinguishing the target forms. These results suggest that explicit instruction affects learners' pronunciation development on compound and phrasal stress. Pedagogical implications of the findings of this study and suggestions for future research are also presented.

목차 (Table of Contents)

• TABLE OF CONTENTS
• TABLE OF CONTENTS ······································································ i
• LIST OF TABLES ············································································· iv
• LIST OF FIGURES ·········································································· vii
• ABSTRACT ···················································································· x
• CHAPTER 1 INTRODUCTION ·························································· 1
• 1.1 Background······································································· 1
• 1.2 The Production Experiment ···················································· 4
• 1.3 Organization ······································································7
• CHAPTER 2 LITERATURE REVIEW ················································· 9
• 2.1 Phrasal Stress ···································································· 9
• 2.1.2 Acoustic Features of Phrasal and Compound Stress ················11
• 2.1.3 Acquisition of Compound and Phrasal Stress by Korean learners
• of English ··································································13
• 2.2 L2 Acquisition of Stress ······················································ 15
• 2.2.1 Studies on Pronunciation Instruction ································· 17
• 2.2.2Form-focused instruction ··············································· 19
• 2.3 Present Study ··································································· 21
• CHAPTER 3 METHODOLOGY ······················································· 24
• 3.1 Research Design ······························································· 24
• 3.1.1Stimuli ··································································· 26
• 3.1.2 Participants ····························································· 29
• 3.1.3 Instruction procedure ················································· 31
• 3.2 Procedure ······································································· 33
• 3.3 Data Measurements ··························································· 33
• 3.3.1 Duration Measurements ·············································· 34
• 3.3.2 Pitch Measurements ··················································· 35
• 3.3.3 Intensity Measurements ·············································· 37
• CHAPTER 4 DATA ANALYSES AND RESULTS ································· 39
• 4.1 Phrasal Stress ·································································· 39
• 4.1.1 Pitch ····································································· 39
• 4.1.1.1 Pitch: the comparisons of the explicit vs. implicit group ·· 39
• 4.1.1.2 Pitch: the comparisons of the explicit vs. native group ···· 43
• 4.1.1.3 Pitch: the comparisons of the implicit vs. native group ···· 47
• 4.1.2 Intensity ································································· 50
• 4.1.2.1 Intensity: Explicit vs. Implicit Group of Learners ·········· 50
• 4.1.2.2 Intensity: Explicit vs. Native groups ························· 53
• 4.1.2.3 Intensity: Implicit vs. Native groups ························· 57
• 4.1.3 Duration ································································ 59
• 4.1.3.1 Duration: Explicit vs. Implicit Groups ······················· 59
• 4.1.3.2 Duration: Explicit Group vs. Native groups ················· 62
• 4.1.3.3 Duration: Implicit vs. Native groups ························· 65
• 4.2 Compounds vs. phrasal stress ··············································· 67
• 4.2.1 Pitch in Compounds and Phrasal Stress ···························· 67
• 4.2.1.1 Pitch: Explicit vs. Implicit groups ···························· 68
• 4.2.1.2 Pitch: Explicit vs. Native speakers ···························· 70
• 4.2.1.3 Pitch: Implicit Group vs. native speakers ···················· 72
• 4.2.2 Intensity in Compounds and Phrasal Stress ······················· 74
• 4.2.2.1 Intensity: Explicit vs. Implicit groups ························ 74
• 4.2.2.2 Intensity: Explicit vs. Native speakers ························ 77
• 4.2.2.3 Intensity: Implicit vs. native speakers ························ 79
• 4.2.3 Duration in Compounds and Phrasal Stress ······················· 81
• 4.2.3.1 Duration: Explicit vs. Implicit groups ························ 81
• 4.2.3.2 Duration: Explicit vs. Native speakers ······················· 84
• 4.2.3.3 Duration: Implicit vs. Native speakers ························ 86
• CHAPTER 5 CONCLUSION ···························································· 89
• 5.1 Discussion ································································ ······89
• 5.2 Limitations and Pedagogical Implication ···································95
• 5.3 Conclusions ·····································································97
• REFERENCES ··············································································· 99
• ABSTRACT in Korean ·····································································103