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C-words and F-words: The importance of distinguishing content and function in teaching second language listening comprehension
System, Vol. 21, No. 4, pp. 495-502, 1993
0346-251X/93 $6.00 + 0.00 © 1993 Pergamon Press Ltd
Printed in Great Britain
C-WORDS AND F-WORDS: THE IMPORTANCE OF DISTINGUISHING CONTENT AND FUNCTION IN TEACHING SECOND LANGUAGE LISTENING COMPREHENSION J O H N K. E A S T M A N
University o f Alicante, Alicante, Spain Grosjean and Gee's prosodic structure theory is applied to second-language listening comprehension. They propose twin parallel interactive segmentation processes which are based on the phonological word: stressed syllables typically found in content words trigger lexical search for meaning, while unstressed syllables are dealt with by a different mechanism. It is argued that second-language students whose mother-tongue is syllable-timed do not have a mechanism to deal with unstressed syllables, and must create one. The initial absence of this mechanism helps explain some of the difficulties students have with listening comprehension. Teaching implications are briefly discussed. INTRODUCTION The learner-listener whose mother tongue is a syllable-timed language faces a major difficulty in learning to deal with the stress-timing of English while listening. In this article, I propose that students' attention should be directed towards the prosodic features of the language as a means of parsing the unbroken string of sound. In syllable-timed languages, the words containing most of the message may be made salient by syntactic re-arrangement, word-stress, tone, pausing (usually after the salient word), etc. Segui et al. (1990) maintain that parsing processes are determined largely by phonology and prosodic structures of a given language, and that French and Spanish are segmented syllabically. It is my contention that, in learning to listen to English, the student must establish a new analysing mechanism in his comprehension system. In stress-timed languages, the message is largely contained in the content words which incorporate one (or two) stressed syllables; the function words are typically unstressed, suffer assimilation or vocalic reduction [and so are very difficult to recognise--Pollack and Pickett (1964)]. Vowel reduction is the major differentiator of English from both its written representation and the syllable-timed languages, whose speakers typically pronounce English phonemically and syllabically. They have considerable difficulty dealing with the frequent indeterminate schwa and short " i " . That is, listeners whose mother-tongue is syllable-timed try to apply the same segmentation process to the English they hear. When we listen to an unknown language, we hear an unbroken string of syllables because we are unable to segment them into words. The same is partly true of the learner-listener; 495
496
JOHN K. EASTMAN
he can segment some o f the syllables into words, but the rest remain as uncomprehended syllables which appear to him to be uttered very rapidly. As his ability to recognise words improves, he reaches a critical point at which he segments a sufficient number of words to give him a context from which he can infer or guess an overall meaning. Before reaching that critical point, the syllable-timed language-speaking learner struggles to process all syllables, first from habit, and second because he does not know which syllables are crucial to meaning. Linguists generally agree that syntactic context plays only a small role in word recognition [e.g. Tanenhaus et al. (1979) and Tyler and Wessels (1983)], because it has been shown that syntax has little limiting effect on form-class and morphological structure of lexical items. However, native listeners have been found to use duration and pitch information to identify syntactic structure before the sentence is complete (Beach, 1991). We may argue that such prosodic information will be unavailable to the second-language listener even if it is taught, given the learner's limited vocabulary, his yet-to-be-learnt ability to predict, his rudimentary knowledge of grammar, and his attentional capacity being devoted (almost) entirely to word recognition. On the other hand, the simplified syntactic nature of the aural material he is exposed to may permit some of the syntactic information to contribute to his parsing process. It is probable that semantic context will give far greater guidance to the learner-listener. In other words, recognizing content words will be the first step the learner makes in comprehension; parsing function words is a skill which emerges much later. This at least is my experience in elementary classes. After playing a tape, I ask elementary students (Ss) what words they have captured: for the most part, they report content words; only later (but still infrequently) do they comprehend adverbials and reduced prepositions and articles. Even intermediate Ss' errors in dictation often relate to unstressed syllables. Likewise, when asked to count the schwas in a short taped passage, elementary Ss typically recognize only about 30o7o on the first trial, rising to only about 50°7o on the second. It is also probable that syntactic and semantic elements provide all o f the learner-listener's clues to comprehension, as other elements available to the native speaker are not yet available to him. For instance, we can infer that the learner-listener's attention is entirely given over to bottom-up processes: attempting to recognize words. This means that he will not have the spare capacity to access any top-down processes (such as prior knowledge of the topic) which would permit him to predict sentence-endings, meanings or topic-related words. Nor has he established any semantic networks which might sensitize other parts of a possible lexicon--in other words, create expectations.
PROSODIC STRUCTURE T H E O R Y Grosjean and Gee (1987) present a word-recognition theory based on prosodic structure that goes a long way in allowing us to understand the difficulties of learners born into a syllable-timed language, and offers the teacher a clearer path to teaching them how to comprehend, rather than being helpless in the face of incomprehension. (Currently, we seem to be able to do little more than introduce the topic, pre-sensitize new vocabulary
C-WORDS AND F-WORDS
497
and present the material.) They argue that researchers have overemphasized the writtenlanguage notion of the word, and question the importance o f the written dictionary (WD) word as a unit o f processing in the early stages of lexical access. Research, they say: has usually investigated the recognition process of single words . . . . and not the operations involved in continuous lexical access . . . . the experimental tasks used in spoken word recognition are too often biased towards single WD-like w o r d s ; . . , this encourages us to think that the human processing system m a y . . , use the WD word as a u n i t . . , of processing (ibid.: p. 137). •
.
.
These authors point out that the importance given to W D words brought with it the following assumptions: (1) (2) (3) all
words are recognized sequentially, word by word and in order; the beginning o f a word is crucial to its recognition, and a word is recognized when its acoustic-phonetic configuration differentiates it f r o m other words (which m a y occur before the end of the word is heard).
Grosjean and Gee argue that assumption 1 m a y not occur with all words, that all the assumptions m a y apply to m a n y content words, but may: • . . not always apply to certain monosyllabic and low frequency words, unstressed function words, words stressed on the second syllable, and words with prefixes and suffixes (ibid." p. 138). l In support of this contention, Grosjean refers to findings from a gating experiment. Gating, first used by Grosjean (1980), is a technique in which: • . . subjects hear successively longer pieces of a word (in increments of 30-50 msec, where a syllable typically lasts 200 msec). After each presentation they say what they believe that the word is (McNeill, 1987: p. 122). Gating, then, empirically establishes the point (often within the word) at which a word is recognized. He cites specifically an experiment (1985) he carried out on sentences of the sort " I saw the plum on the tree", gated f r o m t h e . . , beginning o f " p l u m " , where he found that subjects gave perfect confidence ratings before word-end to only 5~70 o f monosyllabic words, 50~/0 during the following word, 20e/o during the word after that and 25~/0 during the following noun. As far as syllable-timed-speaking second-language learners are concerned, we might also hypothesize that, since schwa is both unknown and, at least initially, difficult for them to parse, words which begin with schwa will present comprehension problems. Grosjean and Gee conclude that the WD word m a y not be the basis of lexical processing and the early stages of lexical access m a y be neither sequential nor word by word. Instead their theory is based on "phonological w o r d s " which " m a y or m a y not correspond to traditional W D w o r d s " . They argue that the main message is normally carried by W D words which are also phonological words, while the rest o f the sentence, made up o f unstressed function words and stressed content words, are grouped into other phonological words. These phonological words are not always constituents in syntactic structure. In, for example:
498
JOHN K. EASTMAN
Anne// might have been quickly/ ironing// clothes/ in the kitchen/ the main message (Anne, ironing, clothes) is contained in phonological words which are also WD words--here marked with double slashes. The other phonological words are composed of stressed WD words with unstressed function words appended, and marked with single slashes. Their theory is supported with only indirect evidence and their presentation is understandably tentative. Basically, they propose that: (1) lexical access is not a WD-word-by-WD-word, strictly left-to-right process, but one which uses the prosodic structure of the speech stream, particularly stressed syllables; (2) two types of analysis seem to take place--lexical search using only the stressed syllable, and a "pattern-recognition-like" analysis of weak syllables. These processes interact constantly with each other and with other knowledge (grammatical, linguistic, situational and world knowledge); (3) the system is a feed-forward, feed-backward one, which is constantly adjusting early or partial analyses and constantly predicting. Thus while the stressed syllable initiates lexical search, simultaneously the weak syllables associated on either side of it (functors, affixes and the weak syllables of content words) are identified by the simpler analytical mechanism. Stressed syllable processing, they argue, is more demanding since it involves finding the appropriate word candidate in the mental lexicon, while weak syllable analysis is more rapid, possibly because a different, smaller " f u n c t o r " lexicon is involved (Fig. 1). Their approach, which grants the stressed syllable central importance, has important implications for lexical access. It may be the stressed syllable, not the first syllable of WD words, which is " l o o k e d u p " in the mental lexicon. The information gleaned from the search will be used to identify the weak syllables (the functors, affixes etc., associated with the stressed syllable). They also emphasize that their bipartite system works on strong or weak syllables, not on content words and function words; a function word might well be processed according to its information load, degree of stress, length, etc., either as if it were a stressed content word or as an unstressed functor. Grosjean and Gee further propose that: (1) Functors may be held both in the general lexicon where they would be treated as words and in a separate lexicon to allow more direct recognition. Strings of functors frequently used together (might've been, I'd have, out of the) might also be held in the functor lexicon as patterns. (2) we should regard the content word/function word not as a dichotomy, but as a continuum, mainly because function words vary in the amount o f stress accorded them: the greater the stress, the more likely they are to be treated as content words. In support of this they cite Cutler and Foss (1977) as finding no reaction-time differences between function and content words when stress was held constant. Now it should be clear that all the elements in Fig. 1 will not be present in the learner-
C-WORDS AND F-WORDS SPEECH
499
I
PERCEPTIONI SYSTEM
(Implicit)
]
KNOWLEDGE of
]
PHONETIC STRING
k
morphophoncmics
W
ng
.sequences
of function words PA'r'I~RN RECOGNITION ] [ L E X I C A L
vs,s
ofw
syllable groups \
\
/l
I t I
I
I j /I
oG :'l
I OW EDGEI I I IMMEDIATE I SITUATION
o,0.
I
Fig. 1. Schematic representation of the listening processes in the native English speaker according to prosodic structure theory. In syllable-timed languages, only the strong syllable sequence would exist.
listener, some being in a rudimentary or very limited state. Furthermore, I have argued (Eastman, 1991) that the beginner's attentional capacity is entirely absorbed by his struggle to decipher the message. This would preclude his access to any top-down information. 2 What is probably available to him is outlined in Fig. 2. We may draw three tentative conclusions from this hypothetical system. First, secondlanguage Ss probably rely for comprehension on content words to a far greater extent than native speakers. By definition, since unstressed syllables are indeterminate and unknown to their ear (and take even native speakers longer to identify), Ss will have to learn how to deal with function words. That is, they will have to learn to carry out the patternrecognition analyses and incorporate this element into their comprehension systems. Second, we may infer from Ss' insistence on stressing all syllables--or avoiding destressing them--while speaking that they may be attempting to reconstitute unstressed syllables to their full salient form while listening, in order to be able to deal with them as content words
500
JOHN K. EASTMAN
SPEECH
t.ot ~ f~llyI
PERCEPTION adapted to { SYSTEM English] {
Weak [being learnt]
Strm 8
I
RULES OF ~..ANGUAGE j [ [basic]
¢ PATl~4a'q RECOGNITION [ ANALYSIS of weak [
(weak-s,ror~) syllable groups
[rudimentary]
I
KNOWLEDGE OF WORLD { [not available] {
[
{ REC(X}NIZH WORD
"" /
[M~ANINOI Fig. 2. Elements of the prosodic system available to the learner-listener. Dashed lines indicate (extremely) limited contribution to the process. The double arrow from weak to strong sequence represents the hypothetical reconstituting treatment students may apply to unstressed syllables before they have developed a functor lexicon.
(see Fig. 2). This makes sense because they have as yet developed no mechanism to deal with unstressed syllables. However, such a reconstituting process would occupy mental energy and divert attention away from recognizing content words, thereby reducing the amount they comprehend and delaying progress in the skill. Third, they may be tolerating a higher level of uncertainty and having to review what they have heard more frequently than they do in their mother tongue.
I M P L I C A T I O N S FOR T E A C H I N G The first conclusion above implies that the teacher must ensure that Ss thoroughly learn to pronounce content words with the weak syllables reduced. He could direct Ss' attention while listening to content words by instructing them to ignore unclear syllables (Ss admit they can do this). The teacher could also explain what psycholinguistic processes are happening as they listen to underline the importance of the differential weak/strong syllable treatment: some of my Ss report that it helps being told this. The second conclusion means that it is equally important to teach them to pronounce functors without stress (most have schwa or short " i " ) , on the unproven argument that
C-WORDS AND F-WORDS
501
if they can hear themselves say it, they will hear others say it. Furthermore, repeating frequent patterns of weak syllabuses--out of the, into an, to the--both isolated and in context--should establish a growing "library" for their pattern-recognition analytical system. The third conclusion involves a personality variable, over which we have no control, and simply entails practice. Finally, we could consider how much easier psycholinguistic research into linguistic mechanisms would have been if the researchers had been speakers of a syllable-stressed, phonemic language and not of English. NOTES lit is unclear how important second-syllable stress is. Cutler (1990) reports that 73o70 of entries in the Medical Research Council psycholinguistic database have first-syllable stress. She also reports a "consistent tendency" to assume word-onset before strong syllables. (Other points of unknown significance but which may have a crucial bearing on segmentation processes are that all words with initial voiced th- are monosyllabic function words, and that most (or all) disyllabic function words have second-syllable stress.) 2An intermediate student, listening to and writing down the words of a Freddy Mercury song, "There must be more to life than this" heard and wrote: in the end, we almost die. At the age of 16, his knowledge of the world is enough for him to know that this should be "we all must die", yet, until I pointed out the anomaly, he did not recognize his error, an indication that top-down knowledge was not available to him during or even after hearing the words. Brown (1977: p. 167) reports a similar experience: foreign teachers of advanced English heard "their expected power cuts"; some reported hearing "their respected power cuts".
REFERENCES BEACH, C. M. (1991) The interpretation of prosodic patterns at points of syntactic structure ambiguity: evidence for cue-trading relations. Journal of Memory & Language 30, 644-663. BROWN, G. (1977) Listening to Spoken English. Harlow: Longman. CUTLER, A. (1990) EXploiting prosodic probabilities in speech segmentation. In Altman, G. T. M. (ed.) Cognitive Models of Speech Processing: Psycholinguistic and Computational Perspectives. Cambridge, MA: MIT Press. CUTLER, A. and FOSS, D. J. (1977) On the role of sentence stress in sentence processing. Language & Speech
20, 55-60. EASTMAN,
J. K. (1991) Learning to listen and comprehend: the beginning stages. System 19, 179-187.
GROSJEAN, F. (1980) Spoken word recognition processes and the gating paradigm. Perception and Psychophysics 28, 267-283. GROSJEAN, F. 0985) The recognition of words after their acoustic offset: evidence and implications. Perception and Psychophysics 38, 299-310. GROSJEAN, F. and GEE, J. P. (1987) Prosodic structure and spoken work recognition. In Frauenfelder, U. H. and Tyler, L. K. (eds), Spoken Word Recognition. Amsterdam: Elsevier Science Publishers. McNEILL, D. (1987) Psycholinguistics: a New Approach. New York: Harper & Row. POLLACK, I. and PICKETT, J. M. (1964) Intelligibility of excerpts from fluent speech: auditory vs. structural context. Journal of Verbal Learning and Verbal Behavior 3, 79-84. SEGUf, J., DUPOUX, E. and MEHLER, J. (1990) Constraining models of lexical access: the onset of word recognition. In Altmann, G. T. M. (ed.) Cognitive Models of Speech Processing: Psycholinguistic and Computational Perspectives. Cambridge, MA: MIT Press.
502
JOHN K. EASTMAN
TANENHAUS, M. K., LEIMAN, J. and SEIDENBERG, M. (1979) Evidence for multiple stages in the processing of ambiguous words in syntactic contexts. Journal of Verbal Learning and Verbal Behavior 18, 427-411. TYLER, L. K. and WESSELS, J. (1983) Quantifying contextual contributions to word-recognition processes. Perception and Psychophysics 34, 409-420.
0346-251X/93 $6.00 + 0.00 © 1993 Pergamon Press Ltd
Printed in Great Britain
C-WORDS AND F-WORDS: THE IMPORTANCE OF DISTINGUISHING CONTENT AND FUNCTION IN TEACHING SECOND LANGUAGE LISTENING COMPREHENSION J O H N K. E A S T M A N
University o f Alicante, Alicante, Spain Grosjean and Gee's prosodic structure theory is applied to second-language listening comprehension. They propose twin parallel interactive segmentation processes which are based on the phonological word: stressed syllables typically found in content words trigger lexical search for meaning, while unstressed syllables are dealt with by a different mechanism. It is argued that second-language students whose mother-tongue is syllable-timed do not have a mechanism to deal with unstressed syllables, and must create one. The initial absence of this mechanism helps explain some of the difficulties students have with listening comprehension. Teaching implications are briefly discussed. INTRODUCTION The learner-listener whose mother tongue is a syllable-timed language faces a major difficulty in learning to deal with the stress-timing of English while listening. In this article, I propose that students' attention should be directed towards the prosodic features of the language as a means of parsing the unbroken string of sound. In syllable-timed languages, the words containing most of the message may be made salient by syntactic re-arrangement, word-stress, tone, pausing (usually after the salient word), etc. Segui et al. (1990) maintain that parsing processes are determined largely by phonology and prosodic structures of a given language, and that French and Spanish are segmented syllabically. It is my contention that, in learning to listen to English, the student must establish a new analysing mechanism in his comprehension system. In stress-timed languages, the message is largely contained in the content words which incorporate one (or two) stressed syllables; the function words are typically unstressed, suffer assimilation or vocalic reduction [and so are very difficult to recognise--Pollack and Pickett (1964)]. Vowel reduction is the major differentiator of English from both its written representation and the syllable-timed languages, whose speakers typically pronounce English phonemically and syllabically. They have considerable difficulty dealing with the frequent indeterminate schwa and short " i " . That is, listeners whose mother-tongue is syllable-timed try to apply the same segmentation process to the English they hear. When we listen to an unknown language, we hear an unbroken string of syllables because we are unable to segment them into words. The same is partly true of the learner-listener; 495
496
JOHN K. EASTMAN
he can segment some o f the syllables into words, but the rest remain as uncomprehended syllables which appear to him to be uttered very rapidly. As his ability to recognise words improves, he reaches a critical point at which he segments a sufficient number of words to give him a context from which he can infer or guess an overall meaning. Before reaching that critical point, the syllable-timed language-speaking learner struggles to process all syllables, first from habit, and second because he does not know which syllables are crucial to meaning. Linguists generally agree that syntactic context plays only a small role in word recognition [e.g. Tanenhaus et al. (1979) and Tyler and Wessels (1983)], because it has been shown that syntax has little limiting effect on form-class and morphological structure of lexical items. However, native listeners have been found to use duration and pitch information to identify syntactic structure before the sentence is complete (Beach, 1991). We may argue that such prosodic information will be unavailable to the second-language listener even if it is taught, given the learner's limited vocabulary, his yet-to-be-learnt ability to predict, his rudimentary knowledge of grammar, and his attentional capacity being devoted (almost) entirely to word recognition. On the other hand, the simplified syntactic nature of the aural material he is exposed to may permit some of the syntactic information to contribute to his parsing process. It is probable that semantic context will give far greater guidance to the learner-listener. In other words, recognizing content words will be the first step the learner makes in comprehension; parsing function words is a skill which emerges much later. This at least is my experience in elementary classes. After playing a tape, I ask elementary students (Ss) what words they have captured: for the most part, they report content words; only later (but still infrequently) do they comprehend adverbials and reduced prepositions and articles. Even intermediate Ss' errors in dictation often relate to unstressed syllables. Likewise, when asked to count the schwas in a short taped passage, elementary Ss typically recognize only about 30o7o on the first trial, rising to only about 50°7o on the second. It is also probable that syntactic and semantic elements provide all o f the learner-listener's clues to comprehension, as other elements available to the native speaker are not yet available to him. For instance, we can infer that the learner-listener's attention is entirely given over to bottom-up processes: attempting to recognize words. This means that he will not have the spare capacity to access any top-down processes (such as prior knowledge of the topic) which would permit him to predict sentence-endings, meanings or topic-related words. Nor has he established any semantic networks which might sensitize other parts of a possible lexicon--in other words, create expectations.
PROSODIC STRUCTURE T H E O R Y Grosjean and Gee (1987) present a word-recognition theory based on prosodic structure that goes a long way in allowing us to understand the difficulties of learners born into a syllable-timed language, and offers the teacher a clearer path to teaching them how to comprehend, rather than being helpless in the face of incomprehension. (Currently, we seem to be able to do little more than introduce the topic, pre-sensitize new vocabulary
C-WORDS AND F-WORDS
497
and present the material.) They argue that researchers have overemphasized the writtenlanguage notion of the word, and question the importance o f the written dictionary (WD) word as a unit o f processing in the early stages of lexical access. Research, they say: has usually investigated the recognition process of single words . . . . and not the operations involved in continuous lexical access . . . . the experimental tasks used in spoken word recognition are too often biased towards single WD-like w o r d s ; . . , this encourages us to think that the human processing system m a y . . , use the WD word as a u n i t . . , of processing (ibid.: p. 137). •
.
.
These authors point out that the importance given to W D words brought with it the following assumptions: (1) (2) (3) all
words are recognized sequentially, word by word and in order; the beginning o f a word is crucial to its recognition, and a word is recognized when its acoustic-phonetic configuration differentiates it f r o m other words (which m a y occur before the end of the word is heard).
Grosjean and Gee argue that assumption 1 m a y not occur with all words, that all the assumptions m a y apply to m a n y content words, but may: • . . not always apply to certain monosyllabic and low frequency words, unstressed function words, words stressed on the second syllable, and words with prefixes and suffixes (ibid." p. 138). l In support of this contention, Grosjean refers to findings from a gating experiment. Gating, first used by Grosjean (1980), is a technique in which: • . . subjects hear successively longer pieces of a word (in increments of 30-50 msec, where a syllable typically lasts 200 msec). After each presentation they say what they believe that the word is (McNeill, 1987: p. 122). Gating, then, empirically establishes the point (often within the word) at which a word is recognized. He cites specifically an experiment (1985) he carried out on sentences of the sort " I saw the plum on the tree", gated f r o m t h e . . , beginning o f " p l u m " , where he found that subjects gave perfect confidence ratings before word-end to only 5~70 o f monosyllabic words, 50~/0 during the following word, 20e/o during the word after that and 25~/0 during the following noun. As far as syllable-timed-speaking second-language learners are concerned, we might also hypothesize that, since schwa is both unknown and, at least initially, difficult for them to parse, words which begin with schwa will present comprehension problems. Grosjean and Gee conclude that the WD word m a y not be the basis of lexical processing and the early stages of lexical access m a y be neither sequential nor word by word. Instead their theory is based on "phonological w o r d s " which " m a y or m a y not correspond to traditional W D w o r d s " . They argue that the main message is normally carried by W D words which are also phonological words, while the rest o f the sentence, made up o f unstressed function words and stressed content words, are grouped into other phonological words. These phonological words are not always constituents in syntactic structure. In, for example:
498
JOHN K. EASTMAN
Anne// might have been quickly/ ironing// clothes/ in the kitchen/ the main message (Anne, ironing, clothes) is contained in phonological words which are also WD words--here marked with double slashes. The other phonological words are composed of stressed WD words with unstressed function words appended, and marked with single slashes. Their theory is supported with only indirect evidence and their presentation is understandably tentative. Basically, they propose that: (1) lexical access is not a WD-word-by-WD-word, strictly left-to-right process, but one which uses the prosodic structure of the speech stream, particularly stressed syllables; (2) two types of analysis seem to take place--lexical search using only the stressed syllable, and a "pattern-recognition-like" analysis of weak syllables. These processes interact constantly with each other and with other knowledge (grammatical, linguistic, situational and world knowledge); (3) the system is a feed-forward, feed-backward one, which is constantly adjusting early or partial analyses and constantly predicting. Thus while the stressed syllable initiates lexical search, simultaneously the weak syllables associated on either side of it (functors, affixes and the weak syllables of content words) are identified by the simpler analytical mechanism. Stressed syllable processing, they argue, is more demanding since it involves finding the appropriate word candidate in the mental lexicon, while weak syllable analysis is more rapid, possibly because a different, smaller " f u n c t o r " lexicon is involved (Fig. 1). Their approach, which grants the stressed syllable central importance, has important implications for lexical access. It may be the stressed syllable, not the first syllable of WD words, which is " l o o k e d u p " in the mental lexicon. The information gleaned from the search will be used to identify the weak syllables (the functors, affixes etc., associated with the stressed syllable). They also emphasize that their bipartite system works on strong or weak syllables, not on content words and function words; a function word might well be processed according to its information load, degree of stress, length, etc., either as if it were a stressed content word or as an unstressed functor. Grosjean and Gee further propose that: (1) Functors may be held both in the general lexicon where they would be treated as words and in a separate lexicon to allow more direct recognition. Strings of functors frequently used together (might've been, I'd have, out of the) might also be held in the functor lexicon as patterns. (2) we should regard the content word/function word not as a dichotomy, but as a continuum, mainly because function words vary in the amount o f stress accorded them: the greater the stress, the more likely they are to be treated as content words. In support of this they cite Cutler and Foss (1977) as finding no reaction-time differences between function and content words when stress was held constant. Now it should be clear that all the elements in Fig. 1 will not be present in the learner-
C-WORDS AND F-WORDS SPEECH
499
I
PERCEPTIONI SYSTEM
(Implicit)
]
KNOWLEDGE of
]
PHONETIC STRING
k
morphophoncmics
W
ng
.sequences
of function words PA'r'I~RN RECOGNITION ] [ L E X I C A L
vs,s
ofw
syllable groups \
\
/l
I t I
I
I j /I
oG :'l
I OW EDGEI I I IMMEDIATE I SITUATION
o,0.
I
Fig. 1. Schematic representation of the listening processes in the native English speaker according to prosodic structure theory. In syllable-timed languages, only the strong syllable sequence would exist.
listener, some being in a rudimentary or very limited state. Furthermore, I have argued (Eastman, 1991) that the beginner's attentional capacity is entirely absorbed by his struggle to decipher the message. This would preclude his access to any top-down information. 2 What is probably available to him is outlined in Fig. 2. We may draw three tentative conclusions from this hypothetical system. First, secondlanguage Ss probably rely for comprehension on content words to a far greater extent than native speakers. By definition, since unstressed syllables are indeterminate and unknown to their ear (and take even native speakers longer to identify), Ss will have to learn how to deal with function words. That is, they will have to learn to carry out the patternrecognition analyses and incorporate this element into their comprehension systems. Second, we may infer from Ss' insistence on stressing all syllables--or avoiding destressing them--while speaking that they may be attempting to reconstitute unstressed syllables to their full salient form while listening, in order to be able to deal with them as content words
500
JOHN K. EASTMAN
SPEECH
t.ot ~ f~llyI
PERCEPTION adapted to { SYSTEM English] {
Weak [being learnt]
Strm 8
I
RULES OF ~..ANGUAGE j [ [basic]
¢ PATl~4a'q RECOGNITION [ ANALYSIS of weak [
(weak-s,ror~) syllable groups
[rudimentary]
I
KNOWLEDGE OF WORLD { [not available] {
[
{ REC(X}NIZH WORD
"" /
[M~ANINOI Fig. 2. Elements of the prosodic system available to the learner-listener. Dashed lines indicate (extremely) limited contribution to the process. The double arrow from weak to strong sequence represents the hypothetical reconstituting treatment students may apply to unstressed syllables before they have developed a functor lexicon.
(see Fig. 2). This makes sense because they have as yet developed no mechanism to deal with unstressed syllables. However, such a reconstituting process would occupy mental energy and divert attention away from recognizing content words, thereby reducing the amount they comprehend and delaying progress in the skill. Third, they may be tolerating a higher level of uncertainty and having to review what they have heard more frequently than they do in their mother tongue.
I M P L I C A T I O N S FOR T E A C H I N G The first conclusion above implies that the teacher must ensure that Ss thoroughly learn to pronounce content words with the weak syllables reduced. He could direct Ss' attention while listening to content words by instructing them to ignore unclear syllables (Ss admit they can do this). The teacher could also explain what psycholinguistic processes are happening as they listen to underline the importance of the differential weak/strong syllable treatment: some of my Ss report that it helps being told this. The second conclusion means that it is equally important to teach them to pronounce functors without stress (most have schwa or short " i " ) , on the unproven argument that
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if they can hear themselves say it, they will hear others say it. Furthermore, repeating frequent patterns of weak syllabuses--out of the, into an, to the--both isolated and in context--should establish a growing "library" for their pattern-recognition analytical system. The third conclusion involves a personality variable, over which we have no control, and simply entails practice. Finally, we could consider how much easier psycholinguistic research into linguistic mechanisms would have been if the researchers had been speakers of a syllable-stressed, phonemic language and not of English. NOTES lit is unclear how important second-syllable stress is. Cutler (1990) reports that 73o70 of entries in the Medical Research Council psycholinguistic database have first-syllable stress. She also reports a "consistent tendency" to assume word-onset before strong syllables. (Other points of unknown significance but which may have a crucial bearing on segmentation processes are that all words with initial voiced th- are monosyllabic function words, and that most (or all) disyllabic function words have second-syllable stress.) 2An intermediate student, listening to and writing down the words of a Freddy Mercury song, "There must be more to life than this" heard and wrote: in the end, we almost die. At the age of 16, his knowledge of the world is enough for him to know that this should be "we all must die", yet, until I pointed out the anomaly, he did not recognize his error, an indication that top-down knowledge was not available to him during or even after hearing the words. Brown (1977: p. 167) reports a similar experience: foreign teachers of advanced English heard "their expected power cuts"; some reported hearing "their respected power cuts".
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J. K. (1991) Learning to listen and comprehend: the beginning stages. System 19, 179-187.
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