The Acquisition Of Lexical Stress In L2 English:An Experimental Study Of Junior High School Students From Henan

L2 English lexical stress plays an important role in the learning and teaching of English as a foreign language in China.Chinese is a syllable-stressed language,which is opposite to English as a typical of stress-timed language in the prosodic continuum of world languages.Due to this typological difference,it is revealed that Chinese L2 English learners often have difficulties in pronouncing L2 lexical stress in English,particularly among young L2 English learners.Moreover,the local dialects of L2 English learners are assumed to play a role in their acquisition of L2 English.Based on this background,the present study intends to explore the acquisition of L2 English lexical stress by junior high school students from Henan Province.Mainly,it focuses on the following research questions via a phonetic experiment:1)To what extent do junior high school students from Henan Province acquire L2 English lexical stress correctly?1)What are the acoustic features of L2 English lexical stress produced by junior high school students from Henan Province?2)What are the typical errors in L2 English lexical stress produced by junior high school students from Henan Province?Two groups of English speakers were recruited in this study:an experimental group（EG）of 30 Grade 8 junior high school students from Henan Province and a reference group（RG）of 2 native British received pronunciation（RP）speakers from the University of Cambridge.The target lexical stress was embedded in four types of English words as stimuli,namely,nonsense word,heteronym,disyllabic word,and trisyllabic word.The recordings of the EG subjects were collected via a professional recorder Zoom H4nPro Handy Recorder in a quiet classroom at a junior high school in Henan province,whereas those of RG subjects were recorded in the sound booth in the phonetic laboratory of University of Cambridge.Then all the data were digitalized,annotated and analyzed acoustically via Praat 6019₆4 and statistically via Excel 2016 and SPSS 22.0.The results of data analyses are as follows:First,the EG subjects’ overall acquisition correct rates（OCARs）of the lexical stress imbedded in all kinds of target words varied significantly.The EG subjects’ overall average OCAR of all English lexical stress was 84.55%.The average OCARs of L2 English nonsense words,disyllabic words,trisyllabic words,heteronyms were 84.67%,87.98%,85.51%,and 81.83%respectively.Trisyllabic nonsense word with stress on the third syllable was best acquired by subjects（92.92%）,and those with stress on the second syllable was least acquired（65.42%）.Second,the results of the acoustic features of EG subjects’ production of target lexical stress are as follows:in terms of pitch,the average pitch values for stressed syllables of EG subjects were significantly higher than those of RP speakers,whereas their average pitch range values were significantly lower than those of RP speakers,demonstrating EG subjects’ incompetence in realizing the stressed syllables with prominent pitch reset.In terms of duration,the mean duration of stressed syllable produced by EG subjects is shorter,whereas,that of unstressed syllable is longer,therefore the stressed-to-unstressed duration ratio is significantly lower,demonstrating EG subjects’ failure to articulate stressed syllables with sufficient duration.In terms of intensity,EG subjects intend to produce significantly stronger intensity of both stressed and unstressed syllable compared to RP speakers,but the stressed-to-unstressed vowel ratios are significantly lower than RP speakers.In a word,EG subjects could signal stressed syllable with higher pitch,longer duration and stronger intensity.However,the stressed syllables articulated by them were with less prominence,and there was a significant difference in the lexical stress produced by EG subjects and English RP speakers.Third,as for the erroneous production of L2 English lexical stress,two kinds of typical errors in the EG subjects’ production were founded.One was stress misplacement and the other was no distinctive prominence between stressed and unstressed syllables.The stress misplacement on the first syllable was usually in EG subjects’ articulation of disyllabic words.The stress misplacement on the second syllable was usually in EG subjects’ articulation of trisyllabic words and heteronyms.The stress misplacement on the third syllable was usually existed in EG subjects’ articulation of trisyllabic nonsense words.Moreover,EG subjects were more likely to produce stressed syllables without sufficient prominence in terms of pitch,intensity and duration.The implications of the above findings are as follows:Firstly,it is necessary to train English teachers and students to be fully aware of the prosodic differences between English and Chinese so that they are ready and able to perceive and produce L2 English lexical stress correctly.Second,both teacher and students of L2 English should be trained systematically so as to understand the function,acoustic features and the rules of specific L2 English lexical stress in citation forms and connected speech.Thirdly,both teachers and students should pay great attention to the typical errors Chinese L2 EFL learners are prone to make in their production so as to avoid them in the daily L2 English teaching and learning.Finally,English teachers should update their technical skill,such as making best use of phonetic software like Praat software,to visualize phonetic rules and enhance daily pronunciation instruction.