SYLLABLE STRUCTURE AND DURATION IN THE REALISATION …1997:SSD.pdf · SYLLABLE STRUCTURE AND DURATION IN THE REALISATION OF GERMAN RHYTHM BY KOREAN LEARNERS1 Sung-Ja Rhie, William

Phonus 3, Institute of Phonetics, University of the Saarland, 1997, 111-141.

SYLLABLE STRUCTURE AND DURATIONIN THE REALISATION OF GERMAN RHYTHM

BY KOREAN LEARNERS1

Sung-Ja Rhie, William Barry & Jacques Koreman

Abstract

Sentences read and imitated by four Korean learners of German, two "advanced"

and two "beginners", containing selected two-, three- and four-syllable words were

compared with readings of the same sentences by two native speakers of German.

The words were also varied systematically in their complexity and in the familiarity

of their syllable structure. They combined familiar and unfamiliar sounds with

known [CV(son)] and unknown [C(C)VC(C)] syllables. The realisations by the

Korean learners were analysed for deviations from the native productions with

respect to pause behaviour, articulation rate, the duration of the selected words, and

the relative syllable duration within those words. Results show that unfamiliar

sounds, syllable structure and Korean syllable-dependent rhythmic patterning

combine to interfere with the production of the correct German rhythm. As the

length and the syllable complexity of the German target words increases so does

the degree of deviation from the native German patterns. Length of exposure to

German did not appear to guarantee a closer approximation to the target patterns,

but all learners were able to modify their L2-productions in the imitation task.

S�tze mit ausgew�hlten zwei-, drei- und viersilbigen W�rtern wurden von vier

koreanischen Deutschlernern gelesen und nachgesprochen, zwei "fortgeschritt-

enen" und zwei "Anf�ngern", und mit Lesungen derselben S�tze durch zwei

deutsche Muttersprachler verglichen. Die Komplexit�t und der Bekanntheitsgrad

der Silbenstruktur dieser W�rter wurden auch variiert. Aus dem Koreanischen

vertraute sowie unbekannte Laute wurden mit bekannten [KV(son)] und

unbekannten [K(K)VK(K)] Silbenstrukturen kombiniert. Die Realisierungen der

1 The present article is a revised and shortened English version of the first author's M.A.dissertation, accepted by the Faculty of Arts of the University of the Saarland in April 1996.

112 Rhie, Barry & Koreman

koreanischen Lerner wurden auf Abweichungen von der muttersprachlichen

Produktion hinsichtlich des Pausenverhaltens, der Artikulationsgeschwindigkeit,

der Dauer der ausgew�hlten W�rter und der relativen Dauer der Silben innerhalb

der W�rter untersucht. Die Ergebnisse zeigen, da§ die weniger vertrauten Laute,

Silbenstrukturen und die im Koreanischen �blichen silbenabh�ngigen rhythmischen

Muster zusammen zur St�rung des korrekten deutschen Rhythmus beitragen. Mit

zunehmender Wortl�nge und Silbenkomplexit�t der deutschen Zielw�rter entfernen

sich die koreanischen Realisierungen weiter von den muttersprachlichen Mustern.

L�ngere Lernzeit scheint keine Garantie f�r eine bessere Approximation zu sein,

aber alle Lerner konnten ihre Zweitsprachenproduktion in der Nachsprechaufgabe

modifizieren.

1. Introduction

It has long been accepted that it is important to train not only the new speech soundsthat have to be mastered in a foreign language, but also the prosodic aspects that aredifferent from the learner's native language. From a coarse definition of prosody asdemarcative (in terms of information grouping), prominence-giving (in terms ofaccenting and focussing) and as a melodic signal of communicative function, it isclear that, generally, prosodic deviations will be perceptually more intrusive thanincorrect speech sounds, which by virtue of their very short duration, are fleetingauditory events. However, it is much more problematical to define the nature of alearner's prosodic difficulties than their segmental problems. With the exception oflexical tones in tone languages, which are clearly defined in their contribution tolexical differentiation, prosodic deviations from an acceptable target form, thoughimmediately noticeable, are frequently more difficult to describe systematically, andare consequently more difficult to correct.

Perceived errors are commonly related to accent placement or inappropriatetonal accent choice. However, it is very difficult to say whether incorrect accentplacement is a systematic problem or the result of other, syntactic problems or generalproblems of formulation; to what extent an apparently wrong tonal accent isinterference from the first language and how much it is the consequence of unnaturalmetacommunicative utterance planning.

Syllable structure and duration in the realisation of German rhythm by Korean speakers 113

A source of prosodic deviation from target-language patterns which is morereadily defined is that which results from differences in the rhythmic languagecategories to which L1 and L2 belong. Although it is not at all clear what factors ofdurational structuring underly the production of the commonly accepted distinctionbetween stress-, syllable-, and mora-timed languages (cf. for example Hoequist,1983a,b), the differing perceptual strategies of members of those language groupsoffer behavioural evidence (cf. Otake et al., 1993) to show that the distinction is morethan a descriptive linguistic abstraction. For speaker-hearers whose cognitiveprocesses are geared to one particular prosodic structuring pattern, it is clearly apotential problem to readjust the subconsciously operating production strategies tofit the chain of syllables into a different pattern.

In stressing the prosodic problems, however, there is a danger of repeating theerror of those who look at the segmental problems of pronunciation withoutconsidering prosody. With the exception of mora-timing, where the definition of therhythmic category is inextricably tied up with the segmental structure of the syllable,there is a tendency to view the rhythmic structure of an utterance from the abstractlevel of syllable sequences. The fact that syllables with differing degrees ofcomplexity have to be fitted into the rhythmic pattern has received little attention,either in terms of theoretical modelling (but cf. Munhall et al., 1992) or in terms ofpronunciation learning (but cf. Ternes, 1978).

This paper explicitly addresses the problems of rhythmic reorganisation inacquiring the pronunciation of a language with a different rhythmic structure, takinginto consideration the effect of different syllable complexity. The first language of thelearners is Korean, a syllable-timed language with a very limited range of syllable-structures: basically a CV-based language, with the possibility of CV + sonorantclosed syllables (cf. Cho, 1967; Kim-Renaud, 1974; Song, 1984). Both open andclosed syllables can have long or short vowel nuclei. Consonant clusters do notoccur, with the exception of initial consonants with the glide approximants /j/ and/w/. The target language is German, a stress-timed language with a very wide range ofsyllable structures (cf. Seiler, 1970; Mangold, 1981). In radical contrast to Korean,consonant clusters occur both in the onset (up to three) and the coda (a maximum offive), and stressable open syllables only occur with long vowel nuclei.


2 . The experiment

2.1. Speakers

Four South Korean students (1 woman, 3 men) served as subjects. Two (henceforthK1 and K2), both 24 years old, who had begun learning German after their arrival inGermany 10 months prior to the investigation are termed "beginners". The other twospeakers (henceforth K3 and K4), 30 and 31 years old, who had spent 6 and 7 yearsin Saarbr�cken, respectively, are considered "advanced". None of the four had pre-pubertary experience of German. Two German speakers (1 woman 31 years old, 1man 30 years old) served as models for the Korean speakers and as a basis forcomparison in the analysis. They will be referred to as G1 and G2.

2.2. Language material

181 words were selected to provide examples of 4 different levels of difficulty interms of phonetic familiarity and syllable complexity for the Korean speakers. Thiswill be referred to as syllable complexity:

Level 1 comprised German sounds which have phonetic equivalents in Korean. Thewords had syllable structures (CV or CV + sonorant) which occur in Korean.

Level 2 comprised German sounds which had no close phonetic equivalents inKorean but retained the simple syllable structure of level one.

Level 3 comprised the sounds from level one which have phonetic equivalents inKorean, but the words had syllable codas with obstruents, and onsets andcodas with obstruent clusters.

Level 4 combined the two unfamiliar aspects of levels 2 and 3, using words withunfamiliar sounds in unfamiliar syllable structures.

The ordering of levels 2 and 3 was not clear a priori, since it is not necessarilythe case that unfamiliar syllable structures made up of phonetically familiar sounds(level 3) are more difficult than familiar syllable structures with phoneticallyunfamiliar sounds (level 2). A second dimension of complexity was contained in the


selection of words, namely the number of syllables in the word. Two-, three-, andfour-syllable words were used.

All the words were produced in the carrier sentence "Ich sagte X wieder" (I saidX again). This non-default order of object (X) and adverb Ð "Ich sagte wieder X" isconsidered to be default Ð was chosen because it provided a non-final position forthe test words. The final position of the adverb "wieder" occurs quite commonly ineveryday spoken German, and the word order was accepted as unproblematical bythe two German native speakers.

2.3. Recordings

The recordings were carried out in two phases:

i) The two German and the four Korean speakers read the 181 test words in thecarrier sentences. The sentences were presented individually on a monitor,placed in the control room in front of the window separating it from therecording room. Noise disturbance from the computer was thus avoided. In thecase of the Korean subjects, unknown words were explained and pronouncedfor them. This, of course, provided an almost immediate auditory model for thespeakers, but not in the sense of repetition as in phase ii; there was aconsiderable pause between explanation and the ensuing recording, and theorthographic form was the prime prompt.

ii) The Korean speakers repeated as accurately as possible the sentences recordedby the German speakers, which were played to them over light earphoneswhich allowed ample auditory feedback from their own production. There wereseveral days between the reading and the repetition task.

2.4. Analysis procedures

A combined approach of auditory and instrumental analysis was pursued.Instrumental analysis, the measurement of sentence, pause, word and syllabledurations, was carried out using the speech pressure waveforms and spectrograms in


cursor-linked windows on a Kay Elemetrics CSL workstation. Where appropriate,statistical tests were carried out using the SPSS program package.

Auditory evaluation was undertaken at two levels:

¥ Firstly, those words which were not produced as the intended target word wereexcluded from further analysis. These occurred almost exclusively during therepetition phase because the words were not available to the Korean subjects inwritten form, and though they had already seen and produced all the wordsduring the reading task, they were not all part of their active, or in some casesfor the beginners even of their passive vocabulary. Since each subject failed torecognize a different number of the 181 originally selected words (K1: 95 words,K2: 61 words, K3: 57 words, K4: 41 words), the final shared corpus containedonly 84 words. The alternative approach of providing orthographic supportduring the repetition task might seem advisable in the light of this shrinkage ofthe data basis, but it was considered imperative to focus the subjects' attentionon the acoustic input and to avoid any chance of orthographic interference.

¥ Secondly, the stress placement and the length and timbre of the stressed vowelwere judged by two trained phoneticians.

3 . Results

The results will be presented and discussed in descending order of duration: a)pausing and articulation rate at sentence level, b) absolute and relative worddurations, c) syllable durations and inter-syllable quotients.

3.1. Sentence level

At sentence level it was decided to deal separately with pausing behaviour and theduration of sentences without pauses ("articulation rate"). The pause analysisprovides an important indicator of spoken-language competence, namely the numberof sentences in which pauses were introduced Ð always before and after the test


word Ð and the duration of those pauses. Both German speakers produced all the"model" sentences without any pauses.

3.1.1. Pause behaviour

Table 1 gives the number of sentences (from among the shared set of 84 sentences)containing pauses, and the average duration of the pause time per sentence. SubjectsK1 and K2 are the beginners, subjects K3 and K4 the advanced learners.

Table 1. Pause frequency and mean pause durations (in ms) for the Korean subjects

Speaker Pause frequency Pause duration

Reading Repet. Total Reading Repet. Total

K1 47 (56) 9 (11) 56 (33) 371 (334) 148 (65) 335 (317)

K2 69 (82) 0 (0) 69 (41) 497 (320) 0 (0) 497 (320)

K3 44 (52) 1 (1) 45 (27) 454 (257) 135 (0) 447 (259)

K4 1 (1) 0 (0) 1 (1) 461 (0) 0 (0) 461 (0)

A link between pausing and the degree of difficulty for the subjects can beexamined in the overall pause frequency and pause duration data differentiatedaccording to complexity level (Level 1-4) and of the number of syllables (2-4syllables). The global data indicate a less systematic effect of complexity level than ofsyllable number (see tables 2 and 3).


Table 2. Pause frequency and mean pause durations for the Korean subjects as a

function of syllable complexity

Complexity level No. (%) of sentenceswith pauses

Mean (sd) pause dur.

Level 1 34 (20) 394 ms (274)

Level 2 45 (27) 449 ms (311)

Level 3 47 (28) 435 ms (328)

Level 4 45 (27) 435 ms (320)

Table 3. Pause frequency and mean pause durations for the Korean subjects as a

function of number of syllables in the word

Number ofsyllables in word

No. (%) of sentenceswith pauses

Mean (sd) pause dur.

2 35 (22) 330 ms (177)

3 62 (25) 424 ms (316)

4 74 (28) 484 ms (342)

Two four-way ANOVAs were performed with pause frequency and pauseduration as dependent variables, and with production task (reading and repetition),learner (K1-K4), syllable complexity level (1-4) and number of syllables (2-4) asindependent variables. For both pause frequency and pause duration there was ahighly significant learner effect (pause frequency: F 50.16; pause duration: F 28.57,df 3, p < 0.001 for both variables) and a highly significant effect of production task(Pause frequency: F 318.75; pause duration F 177.30, df 1, p << 0.001 for bothvariables). Overall, neither pause frequency nor pause duration increases significantlywith syllable complexity, but there is a significant increase in pause duration withnumber of syllables (F 5.72, df 2, p = 0.003), though only between the 2- and 4-syllable condition, as a subsequent one-way ANOVA with post-hoc tests showed..This is also true for the reading task and the imitation task separately.


Subsequent one-way ANOVAs with post-hoc comparisons showed that theadvanced learner K4 had significantly less pauses and lower pause durations than allthe other learners. With regard to pause frequency, K1 (beginner) did not differsignificantly from either K2 (beginner) nor K3 (advanced), but K2 did pausesignificantly more frequently than K3. Pause durations were significantly longer forK2 than for either K1 or K3, who again did not differ.

It is already clear at this stage that the amount of exposure to German is notreflected in clear differences between the beginner and advanced group, at least withregard to pause behaviour.

Overall, neither pause frequency nor pause duration increases significantly withsyllable complexity, but there is a significant increase in pause duration with numberof syllables, though only between the 2- and 4-syllable condition. This is also true forthe reading task and the imitation task separately.

3.1.2. Articulation rate

Articulation rate will be presented and discussed in terms of net sentence duration(sentence duration minus pauses), divided by the number of syllables. Averagearticulation rates for the reading and repetition tasks compared to the nativespeakers' readings of the same sentence set are given in table 4.

A four-way ANOVA testing for effects of learners, syllable complexity, syllablenumber and task on articulation rate showed significant main effects for all fourindependent factors, with significant interactions for learner x production task andlearner x number of syllables (see table 5).


Table 4. Articulation rate (syllables per sec.) for the reading and the repetition

tasks and degree of change (percent) of reading task rate

Speaker Reading Repetition % Change

G1 4.85 -- --

G2 4.99 -- --

K1 3.04 3.69 +21.4

K2 3.18 4.50 +41.5

K3 3.42 4.19 +22.5

K4 4.39 4.36 -0.7

Table 5. ANOVA results for articulation rate as a function of learner, syllable

complexity, number of syllables and production task

Artic. rate F DF Conf. level

Learner (L) 166.52 3 p < 0.001

Syll. compl. (SC) 26.16 3 p < 0.001

No. syllables (SN) 40.91 2 p < 0.001

Prod. Task 453.47 1 p < 0.001

L x PT 2.72 6 p = 0.013

L x SN 78.44 3 p < 0.001

It is clear from table 4 that articulation rate generally increases from reading torepetition (exception K4, who maintains an almost identical rate). However, neitherthe beginners nor the advanced learners actually approximate the native-speakerrates. K2 achieves the greatest increase, progressing from second slowest averagearticulation rate for the reading task to fastest, and closest to the German model forthe repetition task. As with the pause behaviour patterns, the production behaviourof the Korean learners cuts across the degree of experience with German.


Speaking rate was also considered as a function of syllable complexity and ofsyllable number. Tables 6 and 7 show the effect of these factors on the four learnersrelative to the native speakers.

Table 6. Mean articulation rate in syllables per second (sd) as a function of

syllable complexity

Speaker Level 1(n=21)

Level 2(n=21)

Level 3(n=21)

Level 4(n=21)

G1 5.00 (.321) 4.84 (.334) 4.80 (.369) 4.74 (.389)

G2 5.11 (.325) 5.09 (.329) 4.94 (.453) 4.83 (.422)

K1 3.48 (.506) 3.37 (.514) 3.40 (.421) 3.19 (.478)

K2 4.10 (.741) 3.87 (.822) 3.72 (.879) 3.67 (.683)

K3 4.02 (.518) 3.89 (.511) 3.70 (.532) 3.60 (.586)

K4 4.61 (.509) 4.37 (.540) 4.34 (.554) 4.19 (.488)

The overall pattern in the effect of syllable complexity on articulation rate issimilar for the Korean speakers and the native speakers, namely a decrease inarticulation rate with increasing complexity. For the German speakers, however, thechange in articulation rate across complexity is less than for the Korean subjects,level 1 and level 4 differing significantly, whereas for the Korean subjects level 4 issignificantly slower than both levels 1 and 2, and level 1 is significantly faster thanboth levels 3 and 4 (one-way ANOVAs with post-hoc comparisons).

This indicates that the production of unfamiliar syllable structures with familiarsounds (level 3) is more problematical than producing familiar syllable structures withunfamiliar sounds (level 2).


Table 7. Articulation rate in syllables per sec. (standard deviation) as a function

of number of syllables

Speaker 2 Syllables(n = 20)

3 Syllables(n = 31)

4 Syllables(n = 33)

G1 4.59 (.356) 4.82 (.342) 5.02 (.281)

G2 4.78 (.307) 4.93 (.395) 5.17 (.375)

K1 3.18 (.401) 3.39 (.444) 3.44 (.551)

K2 3.68 (.747) 3.77 (.818) 3.99 (.787)

K3 3.64 (.469) 3.80 (.511) 3.90 (.630)

K4 3.99 (.406) 4.42 (.547) 4.58 (.489)

The overall effect of the number of syllables on the articulation rate iscomparable for both the German native speakers and the Korean learners, with therate increasing as the number of syllables in the target word increases. This can beseen as compensation for the increasing number of syllables within the constantrhythmic frame of the carrier sentence. However, the native speakers show asignificant rate increase from 2- to 3-syllable and from 3- to 4-syllable words, whereasthe Korean learners increase their articulation rate significantly from 2- to 3-syllablewords but not from 3- to 4-syllable words. This may be seen as an inability tocompress the longer words into the rhythmic frame. With the exception of subjectK4, the Korean subjects have a much lower rate increase (as well as a generally lowerrate) overall than the German speakers.

3.2. Word level

Since the test words were the controlled production variables, set in a constantcarrier sentence, the word duration data will now be examined in relation to thesentence durations presented in section 3.1.2. The simplest hypothesis is that thepatterns found at the sentence level will be found again, with the much reducedvalues of the word durations, at the word level. In terms of overall effects of the


independent test variables, this is in fact the case. A four-way ANOVA (learners xtask x syllable complexity x no. of syllables) reveals significant main effects for all buttask (see table 8). However, there were also significant learners x task and learner xno. of syllables interactions.

Table 8. ANOVA results for word duration as a function of speaker, syllable

complexity, number of syllables and task

Word duration F DF Conf. level

Learner 75.28 3 p < 0.001

Syll. compl. (SC) 46.90 3 p < 0.001

No. syllables (SN) 241.30 2 p < 0.001

Task 1.81 1 n.s.

Learner x Task 6.11 3 p < 0.001

SC x NS 3.24 6 p = 0.004

However, Table 9, showing the overall word durations for reading andrepetition for the beginners and the advanced learners relative to the native speakersindicates that the relationship between the learners' and the native speakers'realisations is not the same as for sentence durations.

Only in the case of subject K1, whose word durations in the reading task are34% and 29% longer than the two native speakers' is there a significant change inthe repetition task towards the supposed native target durations. The three otherlearners increase their mean word duration during the repetition task, although onlysubject K4 has shorter word durations in the reading task than the native speakersand thus gets closer to the target.


Table 9. Mean word durations in ms (standard deviation) and percent duration

change from reading to repetition

Speaker Reading(n=84)

Repetition(n=84)

% Change

G1 735 (148.5) - -

G2 765 (160.5) - -

K1 987 (266.3) 884 (188.7) - 10.4

K2 788 (191.4) 796 (214.9) + 1.0

K3 809 (187.9) 823 (178.0) + 1.7

K4 680 (175.1) 698 (166.2) + 2.6

Table 10. Mean proportion of net sentence duration (standard deviation) occupied by

the test words, computed as word duration / sentence duration

Speaker Reading(n=84)

Repetition(n=84)

% Change

G1 .43 (.054) - -

G2 .46 (.059) - -

K1 .36 (.073) .40 (.056) 11.1

K2 .30 (.063) .43 (.081) 43.3

K3 .33 (.052) .42 (.054) 30.0

K4 .36 (.060) .37 (.059) 2.8

The different patterns found for the articulation rate at sentence level (comparetable 4) and the above word durations is illuminated by the different proportions ofsentence duration taken up by the nuclear-stressed test words (table 10). It makesclear that comparable word durations for native speakers and advanced learners doesnot imply a correct sentence rhythm. In the expected reflection of stress timing, thenative speakers' test words took up an average 45% of the articulation duration,


whereas for the Korean learners, speakers of a more syllable-timed language, theproportion ranged from 30% and 36% in the reading task, increasing to between37% and 43% in the repetition task. A 4-way ANOVA with the quotient word-duration/sentence-duration (wd/sd) as dependent variable showed highly significanteffects for task (F 230.44, df 1, p << 0.001 ), learner (F 3.32, df 3, p = 0.02 ), syllablecomplexity (F 23.35, df 3, p < 0.001) and (obviously) number of syllables (F 137.11,df 2, p << 0.001). However, there was a significant learner x task interaction (F 41.49,df 3, p < 0.001), reflecting the minimal change in relative word duration for subjectK4 compared to the other three learners.

Table 11. Mean wd/sd quotients (standard deviation) for reading and repetition as

a function of syllable complexity

Speaker Task Level 1(n=21)

Level 2(n=21)

Level 3(n=21)

Level 4(n=21)

G1 (Read) .42 (.047) .42 (.047) .43 (.059) .46 (.054)

G2 (Read) .43 (.056) .45 (.046) .48 (.060) .49 (.054)

K1 Read .33 (.056) .34 (.052) .39 (.093) .38 (.070)

Repet. .37 (.049) .38 (.050) .41 (.052) .42 (.062)

K2 Read .29 (.042) .29 (.065) .29 (.065) .34 (.062)

Repet. .41 (.053) .41 (.102) .43 (.058) .47 (.090)

K3 Read .33 (.042) .32 (.052) .33 (.044) .35 (.068)

Repet. .40 (.043) .41 (.054) .41 (.055) .44 (.057)

K4 Read .33 (.044) .36 (.047) .37 (.066) .38 (.073)

Repet. .34 (.046) .36 (.046) .37 (.065) .40 (.064)

Considering the significant effect of relative complexity of the constituentsyllables (familiar and unfamiliar sounds coupled with familiar and unfamiliarstructure) we see from table 11 that, while increasing complexity results in asystematic increase in the quotient, it has little effect for either beginners or advancedlearners in influencing the degree of approximation to the German values. Indeed


there was no significant speaker x complexity interaction, suggesting a commoncross-language speaker group effect.

Differentiating for reading and repetition, we can also see from table 11 that theminimal change from one task to the other found for subject K4 is independent ofsyllable complexity, as is the large change found for subject K2. As with othermeasures, the behaviour of the Korean learners with respect to the relative durationof the test words does not pattern according to degree of experience with German.

Three of the four learners showed a clear shift in the repetition task towards thenucleus-dominated stress-timing pattern found in the speech of the native Germanspeakers. However, a one-way ANOVA for speaker with post-hoc contrasts showedthat all learners remained significantly different from native speaker 2 and onlysubject K2 achieved sd/wd values equivalent to native speaker 1.

This is in accordance with predictions based on the different rhythmic structuresof German and Korean. The production of more equally weighted syllables in Koreanutterances interferes with the need, in German, to spend a greater proportion of timeon the nuclear than the non-nuclear words in the sentences. The tendency for theadvanced learners' level-1 words to be shorter than those of the German nativespeakers offers supporting evidence for this interpretation.

3.3. Syllable patterning within the test words

The final level of analysis undertaken was the relation between stressed andunstressed syllables within the testwords. In view of the above finding that theKorean speakers spent proportionally less time than the German speakers on theaccent-bearing test words compared to the unstressed words of the carrier sentence,it was predicted that they would show comparable deviations from the Germanpatterning of stressed and unstressed syllables within the test words.

To make a comparison meaningful, however, only words could be used thatwere identifiable as having been produced with a basically correct stress placementand a basically correct number of syllables. This assessment was a separate step andmore differentiated than the original selection of 84 words representing the common


core corpus, which was based solely on the judgment of whether the subjects hadintended to produce the required word. The number of "correct" realisations by all 4subjects was reduced to 37 for the reading task and 61 for the repetition task.

Within this second-level assessment, stress errors were by far the most frequent;segmental errors were commonly unstressed vowel elision and vowel epenthesis inconsonant clusters. There was the occasional categorical vowel quality error whichcombined with a shift in phonemic quantity and thus also precluded comparison. Theauditory judgments necessary for the selection of words for comparison were madeby two trained phoneticians, and the error categories and numbers of wordsexcluded are given in table 12.

Table 12. Number of categorical prosodic and segmental errors during the reading

and the repetition tasks

Speaker Task Prim.stress

Second.stress

Voweldeleted

Vowelepenth.

Segm.quality

Total

K1 Read 6 24 1 3 0 34

Repet. 0 0 10 1 3 14

K2 Read 11 5 6 2 0 24

Repet. 0 1 4 1 1 7

K3 Read 5 10 2 1 2 20

Repet. 0 0 4 2 0 6

K4 Read 1 0 2 4 2 9

Repet. 0 0 2 2 4 8

Total 2 3 4 0 3 1 1 6 1 2 1 2 2

Typical primary stress errors were a shift from later in the word to the firstsyllable:

¥ 'Kommandanten for Komman'danten

¥ 'Mandat for Man'dat


¥ 'Mongolen for Mon'golen

¥ 'Blankett for Blan'kett

This type of stress error is attributable to two causes. Firstly, in terms ofinterference, Korean words are often stressed on the first closed syllable (Song,1984). Secondly, in their German courses, Korean students are given the generalisedstatement that German multisyllabic words tend to be stressed on the first syllable.

More secondary than primary stress errors were made, usually in derivative orcompound words2.

Vowel deletion was the loss of final schwa, or of unstressed /i: y: u:/ after anunvoiced stop or fricative (often between, sometimes after voiceless obstruents). E.g.:

¥ Punkte, Gebilde, Gespr�che, Pfote

¥ Plastizit�t, Psychologie, Architektur, Kapitulant, Anglophilie

Vowel epenthesis is a general problem for Koreans (and speakers of otherlanguage with comparably simple syllable structures). An [é] is inserted betweenconsonants, e.g.:

¥ Konflikt ® [kOnfé'lIkt]

¥ wechselnd ® ['vEks«lént]

¥ Obstbude ® ['Opstébu�d«]

¥ Denkmalkunde ® ['dENkéma�lkUnd«]

3.3.1. Calculation of a "stress quotient"

In order to provide a rough basis for the comparison of Korean and German rhythmicpatterning, a stress quotient (SQ) was derived by dividing the duration of the stressedsyllable (dS) by the mean duration of the unstressed syllables (ds):

i.e., SQ = dS/(ds/Ns)

Although this measure is necessarily sensitive to the segmental structure of thesyllables involved, this was unimportant here because the same inventory of words

2 Typical examples are:Derivatives: Futilit�t, Schwierigkeit, unterschlagen, �berspitzenCompounds: Regenbogen, Obstbude


was used for calculating the quotient for all the speakers. Table 13 gives the meanquotients (and s.d.) for the reading and the repetition tasks.

Table 13. Mean stress quotient (and sd) for the 6 speakers as a function of the task

Speaker Reading(n = 37)

Repetition(n = 61)

G1 1.76 (0.54) 1.76 (0.66)3

G2 1.80 (0.58) 1.83 (0.79)3

K1 1.51 (0.71) 1.97 (1.18)

K2 1.71 (0.85) 1.75 (0.76)

K3 1.66 (0.70) 1.61 (0.58)

K4 1.60 (0.61) 1.69 (0.76)

In the reading task it is noticeable that all four Korean speakers have loweraverage quotients and higher variability than the German speakers. The lowerquotient fulfills the expectation stated at the beginning of this section: the unstressedsyllables occupy a greater proportion of the word. Interestingly, the Korean speakerwhose average stress quotient is closest to the German values (subject K2) is one ofthe beginners, not an advanced learner.

In the repetition task a different picture emerges. Subject K2's overall quotientmust be considered non-deviant, and the advanced learner subject K4 has alsomodified his rhythmic patterning considerably in the direction of the German values.The other advanced learner (subject K3) does not show any such modification, infact the stress quotient is even further removed from the German value range than inthe reading task. The other beginner (subject K1) shows the greatest change fromreading to repetition, overshooting the German value range.

3 These values, used as a basis for comparison of the Korean quotients in the repetition task, arederived from the 61 corresponding words read by the German speakers.


Since the words compared in table 13 are different for reading and repetition(they comprise all the words produced "correctly" by all four Korean speakers ineach of the tasks), the comparison across tasks may be distorted by slightly differinginventories. A second comparison was therefore carried out on the wordspronounced correctly in both reading and repetition task. Since this comparison wasaimed at ascertaining the degree of change achieved by each speaker, the number ofwords used in the comparison was maximised by selecting the correct realisations foreach speaker individually. Table 14 gives the quotients for each Korean speaker andthe values for that particular selection of words for the German speaker who wasused as a model (G1 for K1 and G2 for K2-K4).

Table 14. Mean stress quotient (and sd) as a function of task

Speaker Reading Repetition

K1 (n = 43) 1.69 (0.95) 2.03 (1.26)

German 1 1.81 (0.67) ® ditto

K2 (N = 60) 1.62 (0.85) 1.61 (0.71)

German 2 1.65 (0.61) ® ditto

K3 (N = 62) 1.61 (0.72) 1.56 (0.55)

German 2 1.73 (0.63) ® ditto

K4 (N = 70) 1.59 (0.68) 1.65 (0.73)

German 2 1.80 (0.77) ® ditto

This table confirms that K1 clearly overshot the mark in the degree ofmodification for the repetition task. K2 was very close to the German value for bothtasks. K3 modified his rhythmic patterning in the wrong direction. K4 achieved somedegree of modification in the right direction, but was still considerably off the mark.

The generally lower SQ values for the Korean speakers compared to the Germannative speakers can be interpreted as interference from Korean syllable timing habits.


However, this interpretation is still too global and simplistic. The greater degree ofvariation found in the Korean speakers (in the reading condition) suggests that it isnot simply a case of producing stressed syllables which are (relatively) too shortand/or unstressed syllables that are too long. Figure 1 shows that though this is truefor a majority of the test words, there is a substantial minority of the words with alower German SQ value.

-60% -40% -20% 0 +20% +40% +60% +80%

K4/G2

K4/G1

K3/G2

K3/G1

K2/G2

K2/G1

K1/G2

K1/G1

Figure 1. Percent realisations for which the native-speaker SQ values were lower

and higher, respectively, than the Korean learners' SQ values.

The examination of a selection of specific test words can serve to illuminate thetwo types of deviation from the German model, one with early stress and a finalschwa syllable (see table 15a-b), the other with word-final stress and a precedingunstressed syllable with a full vowel (table 17a-c).


Table 15 a-b. Typical duration patterns for words with final <-en> syllables.

Values in ms, schwa durations in brackets

a) "geben"


Syllable 1 Syllable 2 Syllable 1 Syllable 2

G1 292 223 (0) ® ditto

G2 292 221 (33) ® ditto

K1 337 398 (104) 283 363 (71)

K2 267 319 (127) 241 216 (0)

K3 280 263 (97) 272 268 (83)

K4 241 249 (58) 279 192 (69)

b) "meldeten"


Syllable 1 Syllable 2 Syllable 3 Syllable 1 Syllable 2 Syllable 3

G1 243 100(62) 256(0) ® ditto

G2 282 114(61) 257(0) ® ditto

K1 302 116(63) 410(95) 375 113(74) 363(0)

K2 176 121(52) 318(51) 308 106(86) 344(55)

K3 328 125(74) 349(71) 337 145(86) 344(55)

K4 177 96(34 188(0) 263 124(82) 261(62)

Native speaker 1 elided the schwa completely, producing a syllabic nasal finallyfor both "geben" and "meldeten", native speaker 2 elided the schwa completely fromthe final syllable of "meldeten", while she produced a short (33ms) schwa in thesecond syllable of geben. The SQ values are, however, virtually identical for "geben"


(1.31 and 1.32, respectively), irrespective of the presence or absence of schwa, andfor "meldeten" they are 1.37 and 1.52, repectively.

For "geben", none of the Korean speakers elided the schwa in the reading task,and all the SQ values were too low, three of them less than 1.0, which means that thestressed /ge�/ first syllable was shorter than the unstressed /b«n/ syllable, and thefourth Korean speaker (subject K3), at 1.06, was still markedly lower than the target.The cause of the low SQ value is traceable not just to the much longer schwaduration than for G2, but also to the generally more even "weighting" of syllable 1and syllable 2. In the repetition task, subject K2 did elide the schwa and achieved amuch better quotient, though still much lower than the German models due to aninsufficiently lengthened vowel in syllable 1. Subjects K1 and K3 did not improve thequotient, though they reduced the duration of schwa somewhat. Subject K4increased his SQ by increasing the duration of the stressed first syllable anddecreasing the overall duration of syllable 2 Ð despite a somewhat longer schwa. Inthe case of "meldeten", where there are two unstressed syllables, subject K4 actuallyelided the final schwa in the reading task, and achieved a SQ approaching theGerman models (1.25). Subject K3 achieved an acceptable quotient (1.38) despite noteliding the final schwa, and subjects K1 (1.15) and K2 (0.80) were way below targetvalue with unelided schwa and disproportionately long third syllables. In therepetition task the two beginners increased their SQ values to within (subject K2:1.42) or above (subject K1: 1.58) the range of the German models, and the twoadvanced learners maintained or improved their SQ values.

Table 16a-b deals with a more complex type of word, namely one with a final<-en>, and an unstressed prefix with schwa, namely <be->.

In these words, the German speakers do not elide schwa in the final syllable Ðpossibly in part a consequence of the slightly unnatural reading task Ð but the SQindicates that the stressed syllable is twice as long as the average of the threeunstressed syllables. The Korean speakers' readings of "besch�nigen" haveconsiderably lower SQ values Ð extremely so in the case of speaker K1 Ð and thedurations of prestress and final-syllabe schwa (in <be->) are, with the exception ofK2, much greater. In the repetition task, all but speaker K3 improve their SQ valuesby reducing the schwa durations and increasing the stressed vowel duration.


Table 16 a-b. Syllable (and schwa) durations in ms for the test words

"besch�nigen" and "begnadigen"

a) "besch�nigen"

Speaker Prod. Task Syllable 1 Syllable 2 Syllable 3 Syllable 4

G1 Reading 142 (45) 304 110 201 (51)(Repetition) ditto ditto ditto ditto


K1 Reading 191 (121) 295 136 367 (151)Repetition 174 (91) 339 144 285 (64)




b) "begnadigen"

Speaker Prod. Task Syllable 1 Syllable 2 Syllable 3 Syllable 4








The word "begnadigen" shows a clear difference between the beginners and theadvanced learners in the reading task, the latter approximating the native speaker SQvalues while the beginners' values are much lower. With respect to the schwaduration in the <be-> prefix, the same division between beginners and advanced isapparent, though neither of the advanced learners quite reach the german speakers'values. With the schwa in the final syllable, the division is not clear; K2 and K4 arerelatively close to the German values while K1 and K3 are much longer. In therepetition task, all except K3 reduce the duration of schwa in <be-> and all but K2reduce the duration of the final schwa. The effect of this schwa modification on therepetition-task SQ values is, however, partly accentuated and partly counteracted bychanges in the stressed syllable: K1 and K4 exaggerate its length, resulting in veryhigh SQ values, whereas K3 shortens the stressed syllable as well as the schwas andfinishes up with a lower SQ than for the reading task.

In summary, there is a general tendency to produce schwa-bearing syllables thatare too long and, in some cases, stressed syllables that are too short, giving muchlower SQ values than the German native speakers. This is the basic situation thatwould be predicted from a partial transfer of syllable-timed Korean timing habits ontoGerman. Perception of the deviation from the model, and partial correction of theperceived deviation during the repetition task is apparent, though overcorrection onthe stressed syllable sometimes leads to much higher SQ values than the nativespeakers.

The second category of deviation, representing words which the Koreanspeakers produce with a higher SQ value than the German native speakers, containswords with final-syllable stress preceded by a syllable with a non-reduced vowel, e.g."Advent", "Komplott", "Konflikt". Table 17 a-c gives the syllable durations and SQvalues for these three words.

In the reading task, 8 of the 12 realisations have SQ values that exceed theGerman speakers' values; speaker K4 is the only Korean speaker who falls within theGerman range of values for all three words. The source of the deviating values seemsto lie mainly in the greater length of the stressed syllables (though this is exacerbatedin some cases by a reduced-duration first syllable). This may well be a result of thesyllabic complexity of the stressed final syllables. In contrast to the "schwa" wordsdiscussed above, there does not seem to be any evidence of consistent improvement


Table 17 a-c. Syllable durations for the test words "Advent", "Komplott" and

"Konflikt"

a) "Advent"



G1 157 363 ® ditto

G2 165 357 ® ditto

K1 172 455 129 532

K2 135 459 175 370

K3 141 512 200 447

K4 146 315 261 308

b) "Komplott"



G1 238 401 ® ditto

G2 228 418 ® ditto

K1 268 560 283 580

K2 185 461 192 472

K3 182 561 237 551

K4 172 312 184 358


c) "Konflikt"



G1 229 425 ® ditto

G2 241 482 ® ditto

K1 195 799 206 574

K2 210 518 266 507

K3 280 540 232 521

K4 246 430 227 387

in the repetition task; 5 of the 12 realisations can be judged to be improvements, 4 areworse, and 3 are virtually unchanged (only one of which is close enough to theGerman model to justify the no-change performance).

4 . Summary and Discussion

The rhythmic prosodic performance of four Korean learners of German was examinedat three levels, sentence, word and syllable level, for two tasks which allowedcomparable speech material to be produced by the learners and two native speakers,namely a reading and an imitation task. The material consisted of a 5-syllable carriersentence ("ich sagte ___ wieder"), with a nuclear-accented 2-, 3- or 4-syllable testword. The test words were also graded for syllable complexity , containingcombinations of a) either new sounds or sounds phonetically similar to Koreansounds and b) syllable structures which were either known from Korean or unknownin Korean (= 4 levels of complexity).

At sentence level the learners' pause frequency and duration, and their"articulation rate", measured as number of syllables in the sentence divided by


sentence duration excluding pauses, were compared across tasks, and performance inboth tasks was compared with the German native speakers.

Pause frequency and duration decreased from reading to imitation while thearticulation rate increased. Neither pause frequency nor pause duration wasinfluenced by syllable complexity, but pause duration (though not pause frequency)did increase with increasing number of syllables, possibly reflecting the increaseddecoding and encoding time required for longer words.

Articulation rate increased with the number of syllables in the word butdecreased with syllable complexity. However, whereas the native speakers' rateincreased significantly from 2-syllable to 3-syllable to 4-syllable words, the learnerswere able to increase their rate from 2- to 3-syllable words, but could not accomodatethe required increase for the 4-syllable words in the sentence frame. In contrast tothis, complexity effects were weaker for the native speakers than for the learners:Only between sentences containing words of the least (level 1) and the most complex(level 4) syllable structures was there a significant rate difference. For the Koreanlearners, level 4 was significantly slower than level 2 and 1, and level 4 and 3 wereslower than level 1. These sentence-level results can be interpreted as a reflection ofincreasing difficulty in fitting the longer and more complex word structures into thesentence rhythm.

At word level, three of the Korean subjects had longer durations than the nativespeakers in the reading task, but only one reduced the duration in the imitation task.Apart from the inevitable effect of number of syllables on word duration, there wasalso a significant effect of syllable complexity across all groups. This may be seen as areflection of the greater number of articulatory movements necessary for the morecomplex syllables (closed syllables, consonant clusters). However, the extent of theeffect was greater for the learners (level 4 > levels 3, 2 and 1; level 3 > level 1) thanfor the native speakers (level 4 > levels 2 and 1), indicating that the greaterarticulatory effort invested by the learners.

Absolute word durations do not, however, give an indication of rhythmicproperties, since rhythm is a product of the temporal relations between the elements


of a sequence. The proportion of the sentence taken up by the focussed word givesa better idea of the sentence rhythm determined by the word units. The wd/sdquotient showed that three of the four Korean subjects modified their relative wordduration considerably from reading to imitation, one speaker actually achievingvalues equivalent to one of the native speakers. The effects of syllable complexity onthe quotient values did not appear to be systematically different from those found forthe native speakers.

Syllable level analysis was also carried out in relative terms, relating the durationof the stressed syllable of the test words to the average duration of the unstressedsyllables, giving a stress quotient (SQ). As may be predicted as interference from asyllable-timed to a stress-timed language, the Korean learners produced, on average,stressed syllables that were relatively too short (and/or unstressed syllables that wererelatively too long). As with the other measures, however, there was a clear pattern ofimprovement from reading to imitation. The global values concealed two types ofdeviation from the native German structures, one predominant type corresponding tothe interference prediction, the other diametrically opposed. It was found that wordsbearing final stress and non-schwa vowels in the unstressed syllables were oftenspoken with an overlengthened final stressed syllable, in part a consequence of thecomplex syllable structure perhaps, and often with reduced unstressed syllables. Incontrast to the other type, very little improvement was registered in the imitation task.

In conclusion, we have demonstrated a number of measures to characterisepatterns of prosodic deviation in L2 production. Inasmuch as the preliminaryselection of material for analysis excluded productions that were immediatelyauditorily identifiable as incorrect, we have concentrated on dimensions of foreignaccent which are not readily accessible to direct observation. In keeping with therelational nature of prosodic exponency, the more revealing measures were thequotient relating the sentence-accented word duration to the sentence duration andthe Stress Quotient, which relates the lexically stressed syllable to the unstressedsyllables in a word. Both measures were seen to capture the degree of interferencestemming from the generic rhythm differences between Korean and German. The SQmeasure uncovered two different types of interference, the second of which had notbeen predicted, and may well stem from a combination of syllabic complexity and anon-default stress pattern.


While the number of words excluded from analysis, which reflected the subjects'different lexical command of German, confirmed their grouping into two levels, whichwe labelled beginners and advanced, the prosodic measures showed no suchgrouping. Particularly in their sensitivity to the German model utterances in theimitation task, the subjects behaved as individuals, there being one beginner and oneadvanced subject who consistently showed a clear change of prosodic patterning inthe direction of the German model. Apart from the fact of such known individualdifferences in imitative ability, it was possibly not coincidental that the subject withthe least material excluded from analysis on lexical grounds changed his prosodicpatterning least in the imitative task. In other words, the person with the mostexperience with German was possibly approaching the point of "fossilisation", i.e.was relying on his own internal models of the words and was consequently lesssensitive to the external input provided by the German model to define thepronunciation targets (Markham, 1997, pp. 88 ff.).

5 . References

Cho, S.-B. (1967). A Phonological Study of Korean. Uppsala.

Hoequist, C.E. Jr. (1983a). Durational correlates of linguistic rhythmic categories.Phonetica 40, 19-31.

Hoequist, C.E. Jr. (1983b). Syllable duration in stress-, syllable-, and mora-timedlanguages. Phonetica 40, 203-237.

Kim-Renaud, Y.-K. (1974). Korean Consonantal Phonology. Honolulu.

Mangold, M. (1981). Anlaute und Auslaute im Deutschen. Phonetica Saraviensia 3.Saarbr�cken: Institut f�r Phonetik, Universit�t des Saarlandes.

Markham, D. (1997). Phonetic Imitation, Accent, and the Learner (in series: Travauxde l'Institut de Linguistique de Lund 33). Lund: Lund University Press.

Munhall, K., Fowler, C., Hawkins, S. & Saltzman, E. (1992). "Compensatoryshortening" in monosyllables of spoken English. J. of Phonetics 20, 225-239.

Otake, T., Hatano, G., Cutler, A. & Mehler, J. (1993). Mora or syllable? Speechsegmentation in Japanese. J. of Memory and Language 32, 258-278.


Seiler, H.-J. (1970). Laut und Sinn: Zur Struktur der deutschen Einsilbler. In: H.Steger (ed.). Vorschl�ge f�r eine strukturale Grammatik des Deutschen, 414-428. Darmstadt.

Song, W.-R. (1984). Kontrastive Phonologie: Deutsch-Koreanisch (Dr. Phil.Dissertation Universit�t Freiburg).

Ternes, E. (1978). Der Einflu§ der Silbenstruktur auf die lautliche Interferenz. In: H.W.Wodarz (ed.). Frankfurter Phonetische Beitr�ge II (in series: ForumPhoneticum 16), 93-119.

Documents

SYLLABLE STRUCTURE AND DURATION IN THE REALISATION …1997:SSD.pdf · SYLLABLE STRUCTURE AND DURATION IN THE REALISATION OF GERMAN RHYTHM BY KOREAN LEARNERS1 Sung-Ja Rhie, William