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ACKNOWLEDGEMENTS
I owe an enormous debt of gratitude to my supervisor, Dr. Ha Cam Tam for
her great guidance, precious comments and continuous encouragement from the
beginning and throughout the study process. Without her help, I could not finish my
graduation paper.
My sincere thanks go to all of my teachers of Post-Graduate Studies
Department in University of Languages and International Studies who have brought
me the world of knowledge during my course and helped me complete this
important document.
I also would like to send my appreciation to all of my students studying at
Worldlink English centre for their cooperation and enthusiastic help in recording
the tasks. I am indebted to my colleagues there who always supported and stayed by
my sides when I was in the most stuck.
Last but not least, I wish to send the deepest gratitude to my family for their
endless love and support throughout my life. Without the encouragement of my
grandmother, parents and brothers, I could not have got this far.
I am grateful to all of those who contributed to the completion of this study
and it is an honor for me to receive any comments from the readers.
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ABSTRACT
The research was conducted to examine the most problematic English
consonants facing the students at Worldlink English Centre. Consonantal phoneme
pronunciation error data was collected from the recording using two types of tasks,
namely reading out loud single words and reading out loud a story and analyzed
using narrow IPA phonetic transcription.
The findings indicate that learners at the centre have a tendency to
substitution, deletion and insertion of sounds in syllable-initial, middle and final
positions of the words. Specifically, it was found that the most common error was
sound substitution which most often happened to the affricate, fricative and lateral
sounds: /ʃ/, /ʒ/ and /l/. The second most popular error is called sound deletion,

CHAPTER II: METHODOLOGY 21
2.1. Selection of Informants 21
2.2. Data collection instruments 22
2.3. Data collection procedure 24
2.4. Data analysis procedure 24
CHAPTER III: DATA ANALYSIS AND DISCUSSION 27
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3.1. Sound deletion errors 28
3.2 Sound substitutions 31
3.3. Sound insertion 34
PART III. CONCLUSION 35
1. Conclusion 35
2. Implications 37
3. Limitations and suggestions for further study 38
REFERENCES 40
APPENDIX 1: SINGLE WORDS AND STORY NARROW TRANSCRIPTION I
APPENDIX 2: EXERCISES FOR TAPE RECORDING IV
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LIST OF TABLE, FIGURES AND ABBREVIATION
LIST OF FIGURES
Figure 1: Features of pronunciation
Figure 2: The manner of articulation
Figure 3: The manner of articulation
LIST OF TABLES
Table 1: English Consonant Phonemes
Table 2: Vietnamese initial consonants
Table 3: Vietnamese final consonants
Table 4: The initial consonants of the Hanoian variety
Table 5: Similarities between English and Vietnamese
Table 6: Overview of the consonant errors found in the data

courses at Worldlink English Centre. Basing on the identified errors, the causes,
especially, the influence of mother tongue on learners' pronunciation will be
discussed and some pedagogical suggestions will be provided to improve teaching
and learning English pronunciation courses at the centre.
The study, therefore, answers the following question: What common errors
do students at Worldlink English Centre have in pronouncing English consonants?
1
3. Scope of the study
The main focus of this study is on investigating common errors made by
students in pronouncing twenty four English consonants. Basing on the results, the
question of whether or not Vietnamese language influence the English
pronunciation of the students at Worldlink English Centre is also discussed
and answered.
Participants are 20 non-English major students who are learning basic
pronunciation courses at Worldlink English centre. Textbook for teaching the
course is English Pronunciation in Use – Elementary by Jonathan Marks.
4. Methodology of the study
The data was collected by employing the tool of recording the participants'
pronunciation of single words and story reading. All the data collected are presented
in the form of narrow transcription and then compared to the standard version to
find out the errors. Details of methodology applied in the study are discussed in Part
III - Methodology
5. Design of the study
To achieve the aims of the study, this paper is divided into five chapters.
Part I: Introduction: An introduction consists of the rationale, aims of the
study, scope of the study, method and organization of the study.
Part II: Development
Chapter I: Literature Review: This chapter provides the relevant bodies of
knowledge and gives a brief overview of the literature on the research topic. This
includes key concepts of English pronunciation, intelligibility in pronunciation,

knowledge will be filled.
1.1. English Pronunciation
In order to have an insight into the study, it is necessary to understand the
main features of pronunciation. Pronunciation refers to the production of sounds
that human use to make meaning. Generally, it includes segmental and
suprasegmental aspects. Segmental features are the particular sounds of a language
(segments) while suprasegmental features are aspects of speech beyond the level of
the individual sound, such as intonation, phrasing, stress, timing, rhythm. These are
different aspects of pronunciation but all work in combination when we speak.
Regarding the combination of segmental and suprasegmental features in
pronunciation, Jenkins and Setter (2005, p.1) provide a clearer definition of
pronunciation:
“Pronunciation involves the production and perception of segmental
(sounds), both alone and in the stream of speech, where they undergo number of
modifications and interact with suprasegmental (prosodic) features, particularly
stress and intonation”.
More particularly, Kelly (2000) presented the main features of English
pronunciation in the figure below:
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Figure 1: Features of pronunciation
(Adapted from Kelly, 2000)
1.2. The English Consonants
1.2.1. General description of consonants
Among features of pronunciation, the current study concerns with only
sounds ( or phonemes), particularly the consonants. It is necessary to understand
what the term "consonant" exactly means.
Roach(1983) gives an example in his book English Phonetics and Phonology
to define consonant. “If we make a sound like s or d, it can be clearly felt that we
are making it difficult or impossible for the air to pass through the mouth” (p.10).
Unlike vowel, consonants are the sounds in which there is obstruction to the flow of

place of articulation and voicing, as below:
1.2.2.1. The manner of articulation
The manner of articulation refers to how the sound is made, at the various
locations in the vocal tract.
Figure 2: The manner of articulation
Manner of articulation
Plosive A complete closure is made somewhere in the vocal
tract, and the soft palate is also raised. Air pressure
increases behind the closure, and is then released
‘explosively”.
Affricate A complete closure is made somewhere in the
mouth, and the soft palate is raised. Air pressure
increases behind the closure, and is then released
more slowly than in plosive.
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Fricative When two vocal organs come close enough together
for the movement of air between them to be heard.
Nasal A closure is made by the lips, or be the tongue
against the palate, the soft palate is lowered, and air
escapes through the nose.
Lateral A partial closure is made by the blade of the tongue
against the alveolar ridge. Air is able to flow around
the sides of the tongue.
Approximant Vocal organs come near to each other, but not so
close as to cause audible friction.
1.2.2.2. The place of articulation
The place of articulation identifies where in the vocal tract the sound is
made, and which vocal organs are involved.
Figure 3: The manner of articulation
Place of articulation

r
Palata
l
Velar Glottal
Plosive p b t d k g
Affricate
tʃ dʒ
Fricative f v θ ð s z
ʃ ʒ
h
Nasal m n ŋ
Lateral l
Approximant w r j
1.2.2.4. Phonological Rules
A phonological rule is a method for describing the way in which individual
sounds are produced in spoken language. The sound alternations regularly occur in
connected speech. Phonological rules can be divided into four types: assimilation,
elision and linking. Roach (1983) clearly discussed and demonstrated those types in
his book named English phonetics and Phonology. Firstly, assimilation happens
when a sound changes and one of its features will be more similar to an adjacent
sound. In other words, when two words come together, the sound of one word can
cause changes in sounds belonging to neighboring words. Roach (1983) emphasized
that assimilation "is more likely to be found in rapid, casual speech and less likely
in slow, careful speech".(p.124). The final consonant /t/ in the word that, for
example, will become /p/ before a bilabial consonant, as in: that person
/ðæp
pɜːsən/.
Secondly, in speaking, there are a number of phonemes which are not
actually pronounced and this is called elision. For instance, in words like potato,
tomato, today, the vowel in the first syllable may disappear; the aspiration of the

which are variants of a phoneme. The list of allophonic rules which is based on
Ladefoged's A course in phonetics, page 271, makes clear how to write a consistent
narrow transcription.
1. Consonants are longer when at the end of a phrase.
2. Voiceless stops (i.e., /p, t, k/) are aspirated when they are syllable initial, as in
words such as pip, test, kick [ pʰɪp, tʰest, kʰɪk ].
3. Obstruent -stop and fricatives classified as voiced ( that is, /b, d, g, v, ð, z/) are
voiced through only a small part of the articulation when they occur at the end of an
utterance or before a voiceless sound ( /v/ in try to improve and /d/ in add two)
4. So-called voiced stops and affricates / b, d, g, dʒ/ are voiceless when syllable
initial, except when immediately preceded by a voiced sound ( as in a day compared
with this day).
5. Voiceless stops / p, t, k / are unaspirated after /s / in words such as spew, stew, skew
6.Voiceless obstruents / p, t, k, ʧ, f, θ, s, ʃ/ are longer than their corresponding
voiced obstruents / b, d, g, ʤ, v, ð, z, ʒ/ when at the end of a syllable.
7.The approximants / w, r, j, l / are at least partially voiceless when they occur after
initial / p, t, k /, as in play, twin, cue[ pleɪ, twɪn, kju ].
8.The gestures for consecutive stops overlap, so that stops are unexploded when
occur before another stop in words such as apt[æt ] and rubbed[rʌbd ].
9.In many accents of English, syllable final / p, t, k / are accompanied by a glottal
stop, as in pronunciations of tip, pit[tɪ?p, pɪ?t,]. (This is another case where
transcription cannot fully describe what is going on.)
10.In many accents of English, / t / is replaced by a glottal stop when it occurs
before an alveolar nasal in the same word, as in beaten['bi?n]
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11.Nasals are syllabic at the end of a word when immediately after an obstruent as
in leaden, chasm ['lɛdn,'kæzm]
12.The lateral / l / is syllabic at the end of a word when immediately after a
consonant
12.a. The liquids / l, r / are syllabic at the end of a word when immediately after a

Labial Alveolar Alveo-
palatal
Palatal Velar Glottal
Stop Aspirated ť
Un-aspirated voiceless t
ƫ
ć k
ʔ
voiced b d
Nasal m n
ɲ
ŋ
Fricative Voiceless f s
ʂ
x h
Voiced v z
ʐ ɣ
Nasal I
(Adapted from Duong, 2009)
Table 3: Vietnamese final consonants
Bilabial Alveolar Velar
Stop p t k
Nasal m n ŋ
Non-nasal -w -j
(Adapted from Le Quang Thiem, p.101)
The Vietnamese phonetic system contains 22 initial consonant phonemes:
/b/, /f/ (ph), /v/, /m/, /t/, /d/ (đ), /ť/ (th), /s/ (x), /z/ (d), /n/, /l/, /ƫ/ (tr), /ʂ/ (s), /ć/
(ch), /ɲ/ (nh), /k/ (c, k, q), /ɣ/ (g), /x/ (kh), /ŋ/ (ng), /h/, /r/ (Nguyen, 2009).
According to Duong (2009), three sounds ƫ (tr), ʂ (s), ʐ are not used by Hanoian and
the neighboring provinces. In this study, most of the subjects of this study come

language with the structure of the target language because the influence of native
language in the learners’ target language can be positive and negative.
Basing on the two English consonant and Vietnamese consonant tables, the
researcher found the following similarities and differences:
Generally, most Vietnamese sounds are not much different from English in
terms of pronunciation. There are some initial consonants in English similar to
Vietnamese ones.
Table 5: Similarities between English and Vietnamese
=Vietnamese English
/m/ (m)
/b/ (b)
/v/ (v)
/f/ (ph)
/d/ (đ đ)
/s/ (x)
/z/ (d)
/l/ (l)
/n/ (n)
/k/ (c, k, qu)
/h/ (h)
/m/ (m)
/b/ (b)
/v/ (v)
/f/ (f, ph)
/d/ (d)
/s/ (s, c)
/z/ (z, s, ss)
/l/ (l)
/n/ (n)
/k/ (c, k, qu)

close to the alveolar ridge.
Third, the sound /t/ in Vietnamese-specific consonants, according to Nguyen
(2009), consists the dental “t” as in to “big” and the dental aspirated “t” as in
“rabbit,” which is similar to the English “t” but produced between the teeth. Binh N.
Ngo made a contrast between Vietnamese and English sound /t/. The author states
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that in English the unaspirated /t/ and the aspirated /ť/ are the allophones of the
phoneme /t/. The aspirated /ť/ occurs at the beginning of a stressed syllable, the
unaspirated /t/ in the other positions. For example, in the word taskmaster, the first
consonant t is aspirated /ť/, the second one is unaspirated /t/. Unlike /t/ in English,
the unaspirated /t/ and aspirated /ť/ are different phonemes in Vietnamese that
distinguish the meanings of words: ta (we) ≠ tha (to forgive), tơ (silk) ≠ thơ
(poetry), tư (private) ≠ thư (letter). This may be the reason why learners tend to
confuse Vietnamese aspirated consonant /ť/, which is indicated by the combination
of the two characters th with the English consonants /θ/ and /ð/.
Apart from those similar sounds, there are some different sounds that also
cause difficulty to learners in English pronunciation. The palatal consonant /c/, for
example, is another specific consonant in Vietnamese, which needs to distinguish
with affricate sound /t∫/ in English. Nguyen (2009) indicates that in the production
of this Vietnamese consonant the tongue tip is down near the back of the lower
teeth and contact is made by the tongue blade against the hard palate. The
combination of the characters ch represents the Vietnamese consonant /c/. This
sound should not be mixed up with the English voiceless palato-alveolar
consonant /t∫/, e.g. Vietnamese cha, chú, cho versus English char, choose, chop.
It is possible to see that in the initial position, the sounds that do not exist in
Vietnamese may be the most dominant consonant sounds causing difficulty for
second language learners. They include the sound /tʃ/ in chair, /dʒ/ in judge, /ʃ/ in
shoe and its rare voiced counterpart /ʒ/ in measure, /θ/ as in thing and /ð/ as in this,
and the aspirated sound /t/ in toy. (Nguyen, 2009).
Concerning final-syllable consonants, Vietnamese does exist ending sounds;

speaking learners. “Not only is the sound system of Vietnamese very different from
that of English, but there are also extremely limited opportunities for hearing and
speaking English in Vietnam.” She claims that one of the most striking features of
Vietnamese-accented English is “the elision of consonants, in particular in the
syllable coda” (Cunningham 2009). The reason might be related to the phonotactic
constraints operational in Vietnamese, which is an isolating language (that is, one in
which the words are invariable, and syntactic relationships are shown by word order),
and traditionally, Vietnamese was regarded as monosyllabic because most
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Vietnamese words consist of single syllables (Taffalo, 2001). It is clearly a problem
for Vietnamese learners when pronouncing English which places a ‘heavy semantic
load’ on the coda in verb forms and other suffixes (Cunningham 2009). The
difference of the sound system, in particular in the consonants, between Vietnamese
and English may create errors and result in difficulties in speaking English for
Vietnamese learners as well as for the intelligibility of Vietnamese-accented English.
For example, single final consonants are often absent or substituted with another
consonant which is allowed in the coda in Vietnamese such as the substitution of /p/
for the /f/ at the end of the first syllable in the word if or often, as voiceless stops are
permissible in coda position in Vietnamese while fricatives are not. Moreover, there
is an elision of /z/ in the word is or /d/ in the cluster nds of the word friends that
Vietnamese learners might face (Cunningham 2009).
In this study, the question of whether or not Vietnamese language causes
obstacles to students' pronunciation of English consonants will be answered basing
on the errors they made.
1.6. Intelligibility and Intelligibility problems in pronunciation
The term intelligibility is regularly mentioned in studies about pronunciation.
“ Intelligibility is being understood by a listener at a given time in a given
situation”(Kenworthy, 1987, p.13). In other words, intelligibility is
“understandability”. In pronunciation learning, intelligible speakers are those who
can master their pronunciation to communicate effectively. It may not really native-

differently from how they are by the native speakers that they may affect listeners’
understanding.
1.7. Preview of Previous Studies
There have been great deals of notable works about English pronunciation
issues; however, the researcher pays much attention to the following studies.
In the study entitled “Correcting English consonants commonly
mispronounced by second-year non English majors at ULIS-VNUH”, Vu Doan Thi
Phuong Thao indicated some English consonants which were often mispronounced
by her non-English major students. Accordingly, the sounds /ʒ/,/ʃ/,/tʃ/, were
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difficult to students. They often mistook /ʒ/,/ʃ/ for /z/ and /s/ and the sound /tʃ/ was
replaced with /c/, spelled with c-h, in Vietnamese.
The article entitled “Common pronunciation problems of Vietnamese
learners of English” was written by Dr Ha Cam Tam to answer the question “what
are the most common pronunciation problems of the students in the English
department”. The data was collected through an oral final examination which
required the fourth-year- students to talk about a particular topic in approximately
five minutes. The findings of this study show three common errors of students in
pronouncing English consonants including sound omission, sound redundancy and
sound confusion. Particularly, it is difficult for learners to pronounce the sounds /ʒ,
ʤ, ʧ /, especially these sounds are often replaced by /s/ when they occur at the end
of words.
Unlike the two studies above, which research the wide issues of
pronunciation problem, Dao Thi My Hanh(2007) only focuses on the six certain
consonants: θ/, /ð/, /tʃ/, /dʒ/, /ʃ/, /ʒ/ in her study named “A study on pronunciation
of some English consonants by Vietnamese learners”. In order to find out problems
of the learners at HPMU in pronouncing the six studied consonants, the author
designed two exercises which required students to read out loud and then recorded
their pronunciation. With the support of two foreign teachers of English and
analyzing the data in the light of articulatory phonetics, the author figured out

by teachers.
In short, previous researchers have found out common factors affecting
learners’ pronunciation of English, which are interference of the mother tongue,
inadequate understanding of English sounds, and the lack of effective teaching and
learning. The most common reason found in those studies is the interference of
mother tongue.
The previous research focused only on some consonants with a narrow scope
of context. With a wider context, this paper draws on a study investigating the
errors in pronunciation of consonants made by English learners and possible
explanation of those errors.
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