Non-native patterns of English syllable timing

Journal of Phonetics (1985) 13, 407- 420

Non-native patterns of English syllable timing Z. S. Bond Department of Linguistics, Ohio University, Athens, Ohio 45701, U.S.A .

and Joann Fokes School of Hearing and Speech Sciences, Ohio University, Athens, Ohio 45701, U.S.A. Received 30th March 1985, and in revised form 19th December 1985

This study compared the timing of syllables in the speech of non-native speakers of English with American English timing patterns. The subjects, native speakers of Thai, Malaysian and Japanese, read English words in isolation and with one and two syllable suffixes added. Although the non-native speakers compressed words when producing them with suffixes, they showed little awareness of the English pattern of compressing suffixed words in proportion to the number of added syllables.

1. Introduction

Second language mastery after the age of nine or ten years is possible, but more difficult than for younger learners. Although the syntax and morphology and possibly even the pronunciation of segmentals of the new language can be learned, some aspects of stress and rhythm remain elusive. Perhaps inappropriate timing of syllables contributes to the perceived rhythmic deficiencies of non-native English. In fact, some preliminary data from Nelson (1982) suggest that non-native speakers do not follow the syllable timing patterns of native English speakers. Nelson based his investigation on previous work byLehiste (1972) which studied the relative timing of words in isolation and of the same words when embedded in context, for example when various suffixes are added to them. Lehiste's speakers produced multiple tokens of words such as stick, sticky, sticker, stickily, and stickiness. In such a set of words, the word "stick" is considered the base word while the remainder of the set consists of the base plus a suffix. Lehiste found that her two speakers of American English were quite consistent in their treatment of the duration of the base words with and without suffixes. As the number of syllables in the suffix increased, the duration of the base word decreased. The exact amount of compression of the base word was a function not only of the number of syllables in the suffix but also of the vowel in the syllable nucleus and of the final consonant. Inherently long syllable nuclei, such as fe/ and /i/, were more compressible than short nuclei such as /z/; words ending with voiced consonants were more compressible than words ending in voiceless consonants. In contrast to the American English pattern of base word compression, Nelson ( 1982) 0095--4470/85/040407

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reported that Hindi speakers of English did not shorten base words when these words are spoken with suffixes added. For example, the base compression for the word speed to that of speedy was 0.72 for native English speakers but ranged from 0.86 to 0.92 for the Hindi speakers. In other words, the duration of the base word changed little when suffixed at least according to these preliminary findings. Since timing contributes to the rhythmic naturalness of English, it may be an important parameter differentiating native from non-native speech. The primary purpose of this study, then, was to investigate the timing of words and without suffixes as produced by non-native speakers of English in comparison with the speech of American English speakers. Secondly, since speakers from a number of different language backgrounds were available to serve as subjects, their strategies for dealing with English timing could be compared. The question of interest in this comparison is the generality of non-native timing strategies. Do most non-native speakers adopt similar strategies towards English timing? Are the strategies similar for speakers from the same non-English language background? Or are the strategies primarily specific to individual subjects? 2. Method 2.1 . Subjects

The subjects were six university students enrolled in a class of English pronunciation offered for non-native speakers of English. Their English proficiency in all cases was quite good, allowing them to pursue an academic programme in a university setting. All had demonstrated English proficiency by passing an examination given by the intensive English programme. One of the subjects was a junior, and the remaining six were graduate students. The subjects came from different language backgrounds: two were speakers of Thai, two of Malaysian, and two of Japanese.' None of the subjects reported any difficulty with hearing or speech in their native language. 2.2. Language background In the ideal case, information about the relative timing of syllables would be available for all the languages spoken natively by our subjects, so that predictions about interference could be made directly. Because such detailed information is not currently available, we have attempted to make inferences from more general phonetic descriptions in evaluating the contribution of native language to timing patterns. The most important predictor of timing patterns in a language might be its tendency to employ either syllable or stress timing. In a stress-timed language such as English, considerable adjustment of syllable durations might be expected in order to accommodate a variable number of stressed and unstressed syllables between stress beats. In a syllable-timed language, on the other hand, no such adjustments would be expected. 1 We also recorded one speaker of Yoruba, a syllable-timed language. This speaker compressed base words, but not in proportion to the number of suffixed syllables. His timing patterns therefore resembled those of the Japanese speakers.

Non-native English syllable timing

409

2.2.1. Japanese According to Dauer (1983), Japanese is more like syllable-timed than stress-timed languages, though perhaps it is most accurately characterized as mora-timed. Beckman (1982) reports that Japanese accented and unaccented vowels exhibit minimal differences in duration . Furthermore, Japanese listeners rely primarily on fundamental frequency for prosodic information (Beckman, 1985). Even though Japanese morphology is rich in suffixed particles, we might infer that compressing a base word under suffixation would be counter to Japanese timing patterns. 2.2.2. M alaysian- Indonesian Dauer (1983) lists Indonesian among the syllable-timed languages. There is some tendency for vowel duration in Indonesian to vary with accent and for word-final vowels to be lengthened (Halim, 1974). Words typically consist of two or more syllables but morphological suffixes are rare . Though inferences about timing in Malaysian have to be made with some caution, it would seem that compressing a suffixed base word would not be congruent with Malaysian timing patterns. 2.2.3. Thai Conversational Thai is listed by Dauer (1983) as a stress-timed language. According to Haas (1964, p. xiii), unstressed syllables are "considerably shortened and weakened." Compounding and reduplication are the primary derivational processes, resulting in many polysyllabic words. Thai speakers might be expected, therefore, to vary the duration of stressed syllables. 2.3. Materials The test words employed were the set used by Lehiste (1972): shade, speed, sleep and stick and their forms derived with the monosyllabic suffixes -y, -er, -ing and the bisyllabic suffixes -ily and -iness. These words were originally selected because they are relatively easy to segment from oscillograms. 2.4. Procedure Each subject was given a pack of cards with the test words typed on them. After looking through the cards with the experimenter for familiarization, the subject pronounced each word on each card three times and proceeded through the pack of cards three times, producing nine tokens of each test word. The pack of cards was shuffled after each pass so that the order in which the words were read was random across trials, The recordings were made with high-quality equipment in a small sound-treated room. The tapes were processed by a Fmkjaer-Jensen pitch and intensity meter and displayed by a Siemens Mingograf. The duplex oscillogram was produced at a paper spread of 100 mm s - I . The durations of each base word and of the suffixes were measured from the oscillogram to the nearest 0.5 mm, i.e. to the nearest 5 ms. The segmentation criteria were those outlined by Naeser (1970) which are, in turn, based on Peterson & Lehiste (1960). Briefly, high-frequency noise, displayed as an irregular negative deflection, indicated fricatives; stop release was marked by short duration negative deflections; stop closure was indicated by the presence of minimal acoustic energy; and vowels were marked by periodicity and relatively high amplitude.

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Means and standard deviations of base words and their suffixed forms and of the corresponding syllable nuclei were calculated for comparison with the data for American English speakers reported by Lehiste ( 1972). 3. Results 3.1 . General characteristics The speech of the non-native speakers was first examined for properties which might be affecting the relative length of syllables. In general, their speech was characterized by careful, precise pronunciation of each syllable. There were few segmental mispronunciations. One of the Japanese speakers at times pronounced a very r-like /1/. Only the word shade was consistently mispronounced , with the vowel /'& /, by both Thai speakers. In addition, one of the Thai speakers substituted /tJ/ for /J/ and sometimes used an intrusive fbi (/J'iebd/ or /tJ'iebd/). Although interesting from a contrastive point of view, these segmental differences do not seem to be of the type that would affect the durational relationships between the base word in isolation and the base word with suffixes. The test words are common in American English and we would expect them to be familiar to proficient non-native speakers. In order to examine this assumption in relation to timing, we compared selected non-native productions for possible learning effects. We compared nine pairs of mean base word durations: the means of the first two tokens of the first and last recorded three-word series (three different suffixed words and six speakers, selected at random). If the speakers learned to master the articulation of the test words during the recording session, then their early productions would be slow and halting, and their later ones fluent . Therefore, we would expect the mean of the first pair of words to be greater than the mean of the second pair of words. Though not a general test for articulatory learning, it would be appropriate here, since we were primarily interested in duration comparisons. Our data suggest no practice effects in the nine comparisons. For three comparisons, the first mean was longer than the second; for four, the second mean was longer than the first; for two comparisons, the two means were within !Oms of each other, and hence the same, given the resolution of our measurements (see Table I). 3.2. Duration measurements

The average durations of the base words and the corresponding syllable nuclei in isolation and under suffixation are given in Tables II- VII. In almost all cases, the duration of the base word is greater in isolation than with suffixes. In comparison with the data reported by Lehiste, however, the non-native speakers seem to be less consistent among themselves than native English speakers in the proportion to which they compress the base word. Some other differences between the native and non-native speakers emerge from the tables. The first concerns their treatment of base words. All speakers use an acoustically relatively short vowel in the word stick as would be expected for a word containing a lax vowel before a voiceless consonant. However, for Thai speaker 2 (Table VII), the word stick does not have the shortest overall duration. Only four of the speakers (Malay speaker 2, Table III; Japanese speaker 2, Table VI; Thai speaker 1, Table V) use a shorter vowel nucleus in the word sleep than in either shade or speed, as would be expected

Non-native English syllable timing

411

TABLE I. Means of two early and two late tokens in recording sequence (in ms) Early

Late

Sleeping Japanese Thai Malaysian

Speaker 2 Speaker I Speaker 2

525 435 395

555 418 388

Stickily Japanese Yoruba Malaysian

Speaker I Speaker Speaker 2

360 370 398

370 433 418

Shader Thai Japanese Yoruba

Speaker 2 Speaker I Speaker

523 383 360

560 443 343

TABLE II. Mean durations and standard deviations of the base words and their corresponding syllable nuclei for Malaysian Speaker 1 Word

Duration of base word (ms)

SD

Duration of nucleus (ms)

SD

Shade -er -ing -y -i1y -iness

356 353 378 357 344 337

60 9 15 19 31 32

196 177 176 182 166 148

32 11 8 7 22 14

Speed -er -ing -y -ily -iness

570 448 428 417 405 407

23 25 21 6 38 26

248 170 160 137 138 148

6 17 15 8 7 14

Sleep -er -ing -y -ily -iness

534 485 477 488 430 440

81 43 20 39 28 26

303 254 228 238 195 208

14 35 18 57 13 25

Stick -er -ing -y -ily -iness

485 344 315 353 380 333

21 18 13 15 24 8

113 84 74 68 83 73

4 7 8 10 8 5

of a syllable ending in a voiceless consonant. On the other hand, Malay speaker 1 (Table II) uses a longer vowel in sleep than in speed or shade. Japanese speaker I (Table IV) does not seem to differentiate vowel durations in association with the voicing of final consonants. For Thai speaker 2 (Table VII), the longest vowels occur in the word sleep.

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III . Mean durations and standard deviations of the base words and their corresponding syllable nuclei for Malaysian Speaker 2

TABLE

Duration of base word (ms)

so

Duration of nucleus (ms)

so

Shade -er -ing -y -ily -iness

425 374 342 389 329 319

106 13 31 24 24 22

265 193 188 200 128 133

85 13 29 12 15 II

Speed -er -ing -y -ily -iness

563 374 406 397 353 386

25 40 30 18 24 67

255 110 113 113 137 97

35 15 7 9 18 16

Sleep -er -ing -y -ily -iness

411 423 393 395 411 355

14 15 26 39 32 22

202 128 !51 143 137 107

20 13 10 20 18 14

Stick -er -ing -y -ily -iness

437 403 407 421 392 393

84 5 26 7 41 32

123 76 78 86 75 67

18 9 9 16 7 9

Word

IV. Mean durations and standard deviations of the base words and their corresponding syllable nuclei for Japanese Speaker 1

TABLE

Duration of base word (ms)

so

Duration of nucleus (ms)

so

Shade -er -ing -y -ily -iness

583 406 376 404 353 404

48 48 41 17 31 71

247 176 170 183 !53 !52

42 9 12 6 II 7

Speed -er -ing -y -ily -mess

601 398 409 438 395 380

17 24 19 62 25 15

251 165 !58 163 !58 146

7 13 9 8 9 9

Sleep -er -ing -y -ily -mess

557 426 398 425 397 413

40 22 31 33 25 36

249 207 203 211 188 188

15 23 23 13 14 9

Stick -er -ing -y -ily -mess

442 401 366 401 359 359

57 26 23 27 25 34

98 77 78 77 82 75

7 6 5 8 4 10

Word

Non-native English syllable timing

413

TABLE V. Mean durations and standard deviations of the base words and their corresponding syllable nuclei for Malaysian Speaker 2 Word

Duration of base word (ms)

SD

Duration of nucleus (ms)

SD

Shade -er -ing -y -ily -mess

598 432 443 467 456 404

45 14 10 33 22 38

315 207 218 230 211 202

39 8 4 14 13 10

Speed -er -ing -y -!ly -mess

673 456 461 495 447 436

38 36 16 33 56 27

361 215 213 211 184 190

18 24 8 10 17 8

Sleep -er -ing -y -ily -mess

692 513 540 543 539 445

51 24 22 20 36 40

291 247 253 263 258 221

69 41 11 17 15 20

Stick -er -ing -y -ily -iness

583 423 463 480 417 433

55 24 24 38 23 18

144 87 120 104 102 119

20 17 29 8 25 17

TABLE VI. Mean durations and standard deviations of the base words and their corresponding syllable nuclei for Thai Speaker 1 Word

Duration of base word (ms)

SD

Duration of nucleus (ms)

SD

Shade -er -ing -y -ily -iness

538 358 323 398 315 284

66 34 33 77 23 48

294 170 155 202 131 137

27 8 12 39 13 25

Speed -er -ing -y -ily -mess

590 411 393 440 420 346

22 15 17 66 58 24

260 142 147 169 144 117

20 6 9 28 14 9

Sleep -er -ing -y -ily -iness

579 446 435 437 436 432

30 29 31 23 28 35

232 193 181 173 192 202

19 14 16 18 25 28

Stick -er -ing -y -ily -mess

437 376 435 378 343 342

29 19 31 41 14 24

118 89 93 87 75 107

10 9 14 10 5 44

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TABLE VII. Mean durations and standard deviations of the base words and their corresponding syllable nuclei for Thai Speaker 2 Duration of base word (ms)

SD

Duration of nucleus (ms)

SD

Shade -er -ing -y -ily -iness

574 525 518 481 532 426

63 31 24 109 98 75

249 221 200 203 183 149

19 17 13 33 29 17

Speed -er -ing -y -ily -mess

602 570 573 508 533 445

31 54 79 41 79 35

212 193 185 184 184 131

19 27 17 15 15 24

Sleep -er -ing -y -ily -iness

718 604 578 508 613 500

38 55 20 41 60 49

282 261 242 262 230 200

36 45 29 25 20 46

Stick -er -ing -y -ily -iness

603 447 525 506 442 468

115 48 67 62 46 14

82 98 93 108 82 63

15 16 13 16

Word

II

8

The non-native speakers are inconsistent in the proportion to which they reduce the base word relative to the number of syllables added in the suffixes. According to the Lehiste data, English speakers without exception compress base words more with the addition of any one-syllable suffix. The non-native speakers depart from this pattern. For example, Japanese speaker 2 (Table V) generally decreases the duration of the base word for two:syllable suffixes but with many exceptions such as shadily, sleepiness, and stickiness. The standard deviations of the syllable nuclei and base words of non-native speakers are also considerably greater than those of native speakers. The standard deviations of non-native syllable nuclei extend to 85 ms (Table III); in comparison, the largest native English speaker standard deviation is 28 ms. The non-native standard deviations for base words extend to 115 ms (Table VII) in comparison with 43 ms for native speakers (Lehiste, 1972, pp. 20 19- 2020). These non-native speaker inconsistencies are further illustrated in Figs 1-4. Each figure provides comparisons of the durations of the base words when spoken in isolation, and the proportion by which the base word is compressed when spoken with monosyllabic and bisyllabic suffixes. In each figure, the base word in isolation is arbitrarily assigned the value of 100% . The duration of the base words when produced with suffixes is given as a percentage of the isolated base word. The same figures also show the duration of the syllable nuclei in the base words spoken in isolation in comparison with the syllable nuclei in the base words with suffixes added .

Non-native English syllable timing

415

The syllable nuclei from the base words are assigned a value of 100%, while the syllable nuclei from the suffixed base words are given as proportions of the isolated nuclei. The percentages are calculated from two different durational measurements, the entire base word and the syllable nucleus of the base word. In the figures, the speakers are grouped by native language. Figure 1 gives the durations of base words and syllable nuclei for native speakers of English (redrawn from Lehiste, 1972). The two most salient characteristics of the native speaker pattern are, first, that compression is proportional, dependent on the number of syllables in the suffixes and, secondly, that the syllable nucleus invariably undergoes more compression than the base word. Apparently, the consonants of the base word Subject I, English 25 0

50

shade 64/70 48/60

base +I +2 0

0 base +I +2

I

base +I +2

0 bose +I +2

I

I

I

50

I 100%

75

100%

nuc. 268/word 435 ms

j

I I 50

75

100%

50

75

100%

nuc.

nuc. 180/ word 442 ms

I

I 25

stick 66/79 46/67

75

I

25 sleep 72/83 59/73

I

nuc . 131 /word 402 ms

25

0

100%

I

speed 58/69 38/59

base +I +2

75

50

shade 60/70 47/61 0

I

J

50

Subject 2, English 25 0 base +I +2

100%

nuc. 124/word 491 ms

stick 69/76 62/69

base +I +2

75

nuc. 267 /word 512 ms

25

0

I

I 50

25 sleep 67/82 53/73

100%

I

I

25 speed 54/68 44/62

base +I +2

75

nuc. 266/word 454 ms

50

75

100%

I

nuc. 169/ word 432 ms

I

I

I

Figure 1. Proportional values of the base word and the corresponding syllable nucleus when one (+I) and two ( + 2) syllable suffixes are added for the two

English speakers (taken from Lehiste, 1972). Key to all figures : base, length of base word in I ms; +I, proportion of base to base (with one-syllable suffix); + 2, proportion of base to base (with two-syllable suffix); i, proportional value of syllable nucleus; I, proportional value of base word.

Z. S. Bond and Joann Fokes

416

Subject I , Mo loysion 25

0 bose +I +2

bose +I +2

bose +I +2

bose +I +2

75

100%

I

I

J 75

50

100%

I

nuc. 303/ word 534 m s

I 25

0

50

' 25

sleep 79/90 66/81

I

I

nuc. 248/word 570 ms

speed 63/70 60/71 0

100%

J 25

0

75

50

nuc. 196 /word 365 ms

shade 91/99 80/93

I

100%

75

50

I

nuc . 113 I word 485 ms

stick 66/70 68/74

I

I

I

'

Subject 2, Malaysian 0 bose +I +2

25

bose +I +2

speed 44/98 38/60

0 bose sleep +I 70/98 +2 60/93

stick 67/96 57/90

I

J

I 75

50

100%

nuc. 255/word 563 ms

I

I 25

50

I 50

75

I

100%

75

nuc. 202/ word 411 ms

25

0 bose +I +2

I

25

0

100%

75

50 nuc. 265 /word 425 ms

shade 73/74 49/65

I

I

100%

nuc. 123 I word 437 ms

Figure 2. Proportional values of the base word and the corresponding syllable nucleus when one ( + I) and two ( + 2) syllable suffixes are added for the two Malaysian speakers. See Fig. I for key.

remain relatively unaffected; rather, the vocalic portion is compressed, as shown in the figure. Figure 2 gives the durations of the words and syllable nuclei as produced by two speakers of Malaysian. The first speaker employs minimal compression for the base shade and not much more for sleep. The words stick and speed show compression but not in proportion to the number of syllables in the suffixes. The syllable nuclei are compressed somewhat more than the base, in quite variable proportions from word to word. The second speaker exhibits a different pattern; two base words, sleep and stick, receive minimal compression while shade and speed receive compression comparable to that used by native speakers. The syllable nuclei undergo extensive compression in every word. Compression seems to be unrelated to the quality of the syllabic nucleus or the final consonant.

Non-native English syllable timing

417

Subject I, Japanese 0

bose +I +2

I I

100%

I

I

I

50

75

100%

I

nuc . 249/word 577 ms

I

'

I 25

0

75

nuc . 25 1/wo rd 601 ms

sleep 83/75 76/73

bose +I +2

50

25

0

I

I

I

I

speed 69 / 65 60/ 64

bose +I +2

100%

nuc . 247 /word 583 ms

25

0

75

50

25 shade 72/68 62/65

bose +I +2

50

75

100%

I

nuc . 98/word 442 ms

stick 78/88 80/81

II

I

Subject 2, Japanese shade 69/75 67/72

bose +I +2

50

sleep 87/77 82/71 0

I

I

100%

I

I 75

50

100%

nuc. 291·/word 692 ms

I I 25

stick 72/78 76/73

75

nuc. 361/word 673 ms

25

0

I

I

speed 59/70 52/60

bose +I +2

100%

I

'I

25

0

bose +I +2

75 50 nuc . 3 15/word 598 ms

25

0 bose +I +2

50

I 100%

75

nuc . 144./word 583 ms I

:

I

I

l

Figure 3. Proportional values of the base word and the corresponding syllable nucleus when one (+I) and two ( + 2) syllable suffixes are added for the two Japanese speakers. See Fig. I for key.

Figure 3 represents the production of two speakers of Japanese. Both exhibit the same tendency: to compress the base words under suffixation but with almost no regard for the number of syllables in the suffixes. The syllable nuclei appear to be compressed by approximately the same proportion as the base words, suggesting that consonants must also be undergoing compression. An exception is the word sleep as produced by Speaker 2; for this word, the base is compressed more extensively than the syllable nucleus. The durations of the words for two speakers of Thai are given in Fig. 4. The first Thai speaker seems to compress all base words almost equally, disregarding the number of syllables of the suffixes. The syllable nuclei are also compressed but without a clear relationship between the nucleus and base duration. For the word shade, for example, the nucleus is compressed more, in proportion, than the base. For the word sleep on the other hand, the relationship is reversed. The second Thai speaker compresses the base

418

Z . S. Bond and Joann Fokes Subject I, Thai 0 bose +I +2

25 shade 60/67 45/56

0

I 25

bose +I +2

sleep 79/75 85/74

bose +I +2

:

100%

J J

I 75

50

100%

I

nuc. 232 / word 579 ms

I :

I 25

0

75

50

nuc. 26 0 /word 590 ms

25

0

I

I

I

speed 59/70 50/ 65

bose +I +2

10 0%

75

50 nuc. 294/word 538 ms

50

75

100%

75

100%

nuc 118/word 437 ms

stick 76/90 77/78

Subject 2, Thai 0 bose +I +2

25 shade 83/89 66 / 83

0

I

I 25

sleep 88/ 83 75/78

bose +I +2

50

stick 122/82 95/75

I 75

100% I

I 50

I

I

I

75

100%

nuc . 282/ word 718 ms

I I

II 25

0

I

nuc. 212/word 602 ms

25

0

I

nuc . 249 /word 574 ms

speed 88 / 92 74 / 81

bose +I +2

base +I +2

50

50

75

100%

nuc. 82 I word 603 ms

I

I

I

Figure 4. Proportional values of the base word and the corresponding syllable nucleus when one ( + l) and two ( + 2) syllable suffixes are added for the Thai speakers. See Fig. I for key.

and the nucleus in equal proportions for three of the words. In the word stick, this speaker prolongs the vowel excessively in some words with monosyllabic suffixes. In the remainder of his productions, the base word is compressed more with two-syllable than with one-syllable suffixes in a pattern very similar to that of the native speaker.

4. Discussion All the non-native speakers are similar in that they use some compression of the base words under suffixation. One explanation for this tendency is that compression is a by-product of pre-boundary lengthening. When the base word is spoken in isolation, it is in effect utterance final , hence lengthened. When it is spoken with derivational affixes, it is no longer in an environment in which it is subject to lengthening, and hence appears

Non-native English syllable timing

419

to compress. On the other hand , it is possible that the speakers have learned to compress the base word as a part of learning English. Whichever is the case, in this one respect, the speech of the non-native speakers is similar to that of native speakers. On the basis of our limited knowledge of the phonetic characteristics of our subjects' native language backgrounds, we would predict that native speakers of Thai would tend to approximate English timing patterns reasonably well. On the other hand, native speakers of Japanese and Malaysian would tend to produce syllables at relatively invariant durations. This prediction is supported for three test words for one Thai speaker which seem to match the English patterns. For the Malaysian and Japanese speakers the prediction is supported in the sense that they tend not to match the English pattern, i.e. they tend not to compress base words in proportion to the number of suffixed syllables. The details of English timing patterns for the non-native speakers from the same language background appear similar only for the two native speakers of Japanese. This finding would imply that their English timing patterns are only partially a result of interference (negative transfer) from their native language. Tarone (1978) has suggested that second language phonology shows not only negative transfer but is also characterized by first language acquisition processes such as consonant cluster simplification, overgeneralization, phonetic approximations, and avoidance of difficult targets. Speakers from the same native language background apparently create individual strategies, at least in part, to cope with their new language. Some of the details of the timing patterns described here may very well result from strategies which individual speakers employ in mastering the pronunciation of English. Others may reflect interference from their first languages. It is impossible for us to partition reliably the relative contribution of individual strategies and negative transfer because, to our knowledge, the detailed phonetic data concerning the speakers' native languages are not available. Furthermore, theoretical predictions concerning the phonetic details of interference from first to second language are not overly explicit. All the non-native speakers also employ a slower speaking rate as indicated by word and nuclei durations longer than those found for native speakers. Whether the rate difference is to be attributed to imperfect control of English, to individual speaker variability, or perhaps to experimental variables, cannot be determined on the basis of these data. Although there is much variability among speakers in their treatment of individual base words, there does seem to be, among other factors , one strategy which characterizes their speech more than anything else. Instead of compressing the base word in proportion to the number of syllables in the suffixes, the base word receives about the same amount of compression, regardless of the number of suffixed syllables. These results from a number of different languages suggest that syllable timing may add to the problems of intelligibility of non-native speakers. Their difficulties lie not with compressing base words as such, but rather with consistency and proportion. References Beck man, M . E. (1982). Effects of accent on vowel duration in Japanese, Journal of the Acoustical Society of America, 71 , S23. Beckma n, M . E. (1985). Perceptua l cues to lexical accent contrasts in English and Japanese, Journal of the Acoustical Society of America, 78, S20- S21. Dauer, R. M. (1983). Stress-timing and sylla ble-timing reanalyzed, Journal of Phonetics, 11 , 51 - 62. Halim, A. (1974). Intonation in Relation to Syntax in Bahasa Indonesia. Jakarta: Djambatan.

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