Some English stress mistakes and solutions - A phonetic experimental research on Vietnamese students

International Journal of Language and Linguistics 
2017; 5(2): 39-49 
doi: 10.11648/j.ijll.20170502.13 
ISSN: 2330-0205 (Print); ISSN: 2330-0221 (Online) 
Some English Stress Mistakes and Solutions - A Phonetic 
Experimental Research on Vietnamese Students 
Tran Thi Thanh Dieu 
Faculty of English Linguistics and Literature, University of Social Sciences and Humanities, Viet Nam National University, Ho Chí Minh City, 
Vietnam 
Email address: 
thdieu2003@yahoo.com, thanhdieutt@hcmussh.edu.vn 
To cite this article: 
Tran Thi Thanh Dieu. Some English Stress Mistakes and Solutions - A Phonetic Experimental Research on Vietnamese Students. International 
Journal of Language and Linguistics. Vol. 5, No. 2, 2017, pp. 39-49. doi: 10.11648/j.ijll.20170502.13 
Received: February 26, 2017; Accepted: March 10, 2017; Published: March 27, 2017 
Abstract: The combination of phonological knowledge with rhythm and English stress rules is one of the solutions for English 
stress problems facing Vietnamese students. From the phonetic experiment, some types of stress mistakes made by Vietnamese 
students were discovered. The hypothesis is that the English Rhythmic patterns and English stress rules will help students to 
solve their stress problems. However, the English stress rules are so complicated. Therefore, based on the main rhythmic pattern, 
the key for stress rules has been raised to simplify the way to recognize stressed syllables. The final target is to help Vietnamese 
students identify English words through different ways of stress placement in order to increase their pronunciation ability as well 
as catching the main idea in the conversation to improve their communicative skill in English. 
Keywords: English Rhythmic Pattern, Complex Rhyme, Heavy Syllable, English Stress Rules, Phonetic Experiment 
1. Introduction 
No one can deny that every language in the world has its 
own characteristic speech rhythm. English tends to be a 
stress-timed language with rhythmic patterns based on a fairly 
regular recurrence of stressed syllables [ 3]. However, 
Vietnamese tends to give equal weight to each syllable 
[ 4, 29, 30]. As a result, many students often use the 
Vietnamese rhythmic pattern when speaking English. In 
addition, Vietnamese language has mono-syllabic words while 
English words are multi-syllabic. Therefore, they are the main 
reasons leading to stress problems facing Vietnamese 
students. 
To solve this problem, it is important for students to know 
the different rhythmic patterns between Vietnamese and 
English. Moreover, the English stress rules are so complicated 
that it is not easy for Vietnamese students to recognizer stress 
syllables in English multi-syllabic words. Therefore, the paper 
aim to simplify the English stress rules mainly based on the 
English rhythmic characteristics and types of English stress 
mistakes recognized through phonetic experiment made by 
Vietnamese students. 
2. Methodology 
The research was conducted for twenty–four weeks from 
January 2012 to June 2012 with six weeks for preparation and 
choosing population, twelve weeks for phonetic experiment, 
and the last six weeks for data analysis. The method used in 
the research is the comparative strategy based on the prosodic 
analysis of Rhythmic patterns between English and 
Vietnamese, as well as the combination of quantitative 
approach and phonetic experimental approach to find out 
students’ stress mistakes and solutions. 
The word samples were recorded from the ‘Oxford 
Advanced Learner Dictionary’ ‘Cambridge Advanced Learner 
Dictionary’ and ‘Multi-Dictionary version 9.0 HuyBiên 2008’, 
called standard pronunciation (Cáchphátâmchuẩn = CPAC) or 
RP (Received pronunciation) and from the population 
(students), called investigating samples (Mẫukhảosát = MKS) 
or T (Token). The data was analyzed and illustrated by 
SPEECH ANALYZER (Copyright © 1996-2007 by SIL 
International) and PRAAT 5.05.12. (copyright @ 1992-2008 
by Paul Boersma and David Weenink). 
40 Tran Thi Thanh Dieu: Some English Stress Mistakes and Solutions - A Phonetic Experimental 
Research on Vietnamese Students 
3. Data Analysis and Finding 
3.1. Comparison Between English and Vietnamese 
Rhythmic Patterns 
“English is a Stress-timed language, with the rhythmic 
pattern based on the regular repetition of the stressed syllables. 
Whereas, Vietnamese tends to have the equal syllable to form 
the Rhythmic pattern of the Syllable-timed language, with the 
syllables having the equal intensity” [[3]]. Therefore in the 
paper “A case study of solutions to some stress mistakes made 
by Vietnamese students - a phonetic experimental research” 
by Dr. Tran Thi Thanh Dieu, a table of comparison between 
the English and Vietnamese rhythmic patterns has been 
summarized as follows [[6]]. 
Table 1. Comparison of the English and Vietnamese Rhythmic Patterns. 
ENGLISH RHYTHMIC 
PATTERN 
VIETNAMESE 
RHYTHMIC PATTERN 
Type of 
language 
Stress-timed language, with 
the rhythmic pattern based 
on the regular repetition of 
the stressed syllables 
Syllable-timed language, 
with the syllables having 
the equal intensity, 
Pattern {F = [S W]} {N = [A]} = {R ==[S]} 
Meaning of the 
abreviation 
F = Foot N = nhịp (= Rhythm) 
S = strong W = weak A = âm tiết (= syllable) 
The foundation of the English rhythmic pattern is the existence 
of the 2 types of syllable: heavy and light syllable. A light syllable 
contains only a short vowel in the rhyme, with no coda, as in the 
first syllable of the word “about” because onsets are entirely 
irrelevant to the calculation of syllable weight [[18]]. If a syllable 
has a complex rhyme, then it is heavy; and complexity of rhyme 
can be achieved in two different ways. First, a heavy syllable may 
have a short vowel, but one or more coda consonants, as in the 
word “bet, best”. Second, it may have a branching nucleus, 
consisting of a long vowel or diphthong; such a syllable will be 
heavy whether it also has a bled coda, as the second syllable of 
the word [chor ale] and as it put by the Cambridge advance 
learner dictionary – third edition “when a word or syllable is 
pronounced with greater force than other words in the same 
sentence or other syllables in the same word, it is stressed”, as 
well as Fry (1955, 1958)’s identified the intensity over the 
syllable as a possible acoustic correlate of stress differences. 
3.2. Phonetic Experiment for Mistakes Recognization and 
Solutions 
3.2.1. Phonetic Experiment Proving the Mistakes on English 
Word Stress Made by Vietnamese Students 
A spectrogram as the one below is created by displaying all 
of the spectra computed from the speech waveform together. 
The vertical axis in a spectrogram represents frequency, with 0 
Hz at the bottom. The lines visible in the spectrogram on this 
page each represent 1000 Hz along the frequency axis, so that 
the spectrogram contains 8000 Hz in total. All of the spectra 
computed by the Fourier transform are displayed parallel to 
this vertical or y-axis. The horizontal axis represents time; as 
we move right along the x-axis we shift forward in time, 
traversing one spectrum after another. Spectrograms are 
normally computed and kept in computer memory as a 
two-dimensional array of acoustic energy values. For a given 
spectrogram S, the strength of a given frequency component f 
at a given time t in the speech signal is represented by the 
darkness or color of the corresponding point S(t,f). Therefore, 
RP = CPAC (Cáchphátâmchuẩn: received pronunciation 
/standard pronunciation) and IS = MKS (Mẫukhảosát: token/ 
investigated sample) of many words of all types were recorded 
and investigated by phonetic experiment providing the result, 
in which the word [chorale] has been chosen for illustration as 
the following spectrogram figures. 
Figure 1. Spectrogram of the Pitch and Intensity comparison between RP and IS. 
 International Journal of Language and Linguistics 2017; 5(2): 39-49 41 
Table 2. Comparison of the Intensity and Pitch between RP and IS. 
MAXIMUM NUMBER RP IS 
INTENSITY 
SYLLABLE 1 60.66 dB 66.24 dB 
SYLLABLE 2 72.60 dB 67.05 dB 
PITCH 
SYLLABLE 1 183.7 Hz 
SYLLABLE 2 107 Hz 
As it put by the Cambridge advance learner dictionary – 
third edition “when a word or syllable is pronounced with 
greater force than other words in other syllables in the same 
word, it is stressed”, as well as Fry (1955, 1958)’s identified 
the intensity over the syllable as a possible acoustic correlate 
of stress differences, according to the number in the table and 
the spectrogram figures above, the intensity of RP = CPAC at 
the first syllable peak is 60.6dB and at the second syllable 
peak is 72.60 dB, therefore, we can have the conclusion that 
RP pronounced with a greater energy at the second syllable 
than at the second syllable (72.60 dB - 60.66 dB = 12.06dB) 
and made the English rhythm pattern as {F = [S W]}. Whereas 
the intensity of IS = MKS at the first syllable peak is 66.24 dB 
and at the second syllable peak is 67.05 dB, nearly the same 
intensity at the peak of the stressed and un stressed syllable 
(67.05 dB - 66.24 dB = 0.81dB), which is a serious mistake 
caused by the influence of Vietnamese mother tongue, called 
interfering mistake in language with the Vietnamese rhythmic 
pattern as {N = [A]}. In addition, the pitch can’t be used as the 
cue identifying stress syllable but just shows the accent type of 
the speakers. 
To find out the types of English stress mistake made by 
Vietnamese students, 12 groups of IS from the Northern, 
Central and Southern of Vietnam have been recorded their 
pronunciation of the all kinds of English words, as follows. 

 Simple words: multi-syllabic words without affix of 
Noun, Adjective, Verb. 

 Complex words: multi-syllabic words with affix. 

 Compound words: with 2 roots. 
The result of the disyllabic word [chorale] pronounced by 
12 groups of IS is used to illustrated the 3 types of English 
stress mistake made by Vietnamese students. 
Table 3. Intensity and Pitch mean of RP and IS in the phonetic experiment. 
No Mistake-type Group 
Intensity mean Mistake-type and the number of 
IS in every group/ 100 
Pitch Difference 
mean Syllable 1 Syllable 2 Difference 
CPAC/ RP 62.90 dB 72.60 dB 9.70 dB EXACT 107 Hz 
1 T_9 66.51 dB 67.06 dB 0.55 dB A 
33.33% 
183.7 Hz 
2 T/MKS_12 69.13 dB 70.03 dB 0.9 dB A 189.4 Hz 
3 T_7 62.14 dB 65.52 dB 3.38 dB A 176.5 Hz 
4 T_5 62.21 dB 65.25 dB 3.04 dB A 123.5 Hz 
5 T_10 66.22 dB 56.02 dB -10.2 dB B 
16.6 6% 
122.2 Hz 
6 T_1 75.11 dB 60.01 dB -15.1 dB B 163.1 Hz 
7 T_8 72.01 dB 69.28 dB -2.73 dB AB 
25% 
103.6 Hz 
8 T_6 64.03 dB 62.04 dB -1.99 dB AB 199 Hz 
9 T_2 67.11 dB 65.55 dB -1.56 dB AB 163.2 Hz 
10 T_3 61.22 dB 67.88 dB 6.66 dB 
Adapt 50 -69% RP 16.6 6% 
122.7 Hz 
11 T_4 65.04 dB 73.05 dB 8.01 dB 192.4 Hz 
12 T_11 59.21 dB 68.82 dB 9.61 dB Adapt 70 -90% RP 8.33% - 111.3 Hz 
Figure 2. Comparison between RP Intensity and intensity difference among 12 TOKEN groups. 
42 Tran Thi Thanh Dieu: Some English Stress Mistakes and Solutions - A Phonetic Experimental 
Research on Vietnamese Students 
3.2.2. Types of English Stress Mistake 
From the phonetic experiment above, three types of English 
stress mistakes have been recognized 
Type 1: Rhythmic error (A) 
Right stress placement but nearly the same force for the two 
syllables, not adapt the Rhythmic Pattern {F = [S W]}. 
The two IS (MKS) adapted 50 -69% RP (CPAC), equal to 
16.66% since the intensity difference (ID) between the 2 
syllable peaks of IS_3 = 67.88 dB – 61.22 dB = 6.66 dB and ID 
between the 2 syllable of IS_4 = 73.05 dB – 65.04 dB = 8.01 dB. 
Therefore, there was no mistake of stress placement. However, 
this intensity difference can not lead to one strong syllable and 
one weak syllable of the Rhythmic pattern {F = [S W]}. 
Therefore, this is the illustration for the Rhythmic error (A). 
Figure 3. The intensity difference between the 2 syllable peaks of the word [chorale] between RP and IS_3,4. 
Type 2: Wrong placement of stress (B) 
Gaining the percentage 16.66% is the two investigated 
samples having the intensity difference between the 2 syllable 
peaks from 10p to adapt the Rhythmic pattern {F = [S W]}. 
However, the intensity difference between the two syllable 
peaks of IS_1 = 60.01 dB - 75.11 dB = - 15.1dB and between 
the two syllable peaks of IS_10 = 56.02 dB – 66,22 dB = - 10.2 
dB, to illustrate that the two investigated samples place stress 
on the 1st syllable to make the stress placement mistake (B). 
Figure 4. The intensity difference between the 2 syllable peaks of the word [chor ale] between RP and IS_1,10. 
ĐỐI CHIẾU HIỆU SỐ CƯỜNG ĐỘ 2 ĐINH ẨM TIẾT GIỮA CPAC VÀ MKS 3, 4
0
10
20
30
40
50
60
70
80
1 2 3 4 5
sec
d
B
CPAC
MKS_3
MKS_4
ĐỐI CHIẾU HIỆU SỐ CƯỜNG ĐỘ 2 ĐINH ẨM TIẾT GIỮA CPAC VÀ MKS 1, 10
0
10
20
30
40
50
60
70
80
1 2 3 4 5
sec
d
B
CPAC
MKS_10
MKS_1
 International Journal of Language and Linguistics 2017; 5(2): 39-49 43 
Type 3: The combination of type 1 and type 2: (A + B) 
Rhythmic error (A) and Wrong placement of stress (B). 
One more mistake type is the combination of the Rhythmic 
error (A) and the wrong placement of stress (B), having 25%, 
since the intensity difference between the two syllable peaks 
of IS_8 = 69.28 dB - 72.01 dB = -2.73 dB, IS_6 = 62.04 dB - 
64.03 dB =, -1.99 dB HSCĐ and T_2 = 65.55 dB - 67.11 dB =- 
1.56 dB to illustrate the wrong placement of stress while 
placing stress at the 1st syllable. Moreover, the intensity 
differences <3, showing the unablility of adapting the 
Rhythmic Pattern {F = [S W]}, to compare with the intensity 
difference between the two syllable peak of RP = = 72.60 dB - 
62.90 dB = 9.70 dB > 5. 
Figure 5. The intensity difference between the 2 syllable peaks of the word [chorale] between RP and IS_2,6,8. 
3.2.3. Solution 
Rhythm is so important to language with multi-syllabic 
words that children have to learn the rhythm of their L1 
very early in life [[12]]. By the time they reach the age of 
one, that rhythm is deeply familiar to them, and they will 
unconsciously apply it to any L2 that they learn (Aoyama et 
al. 2007). Since English learners will be predisposed to use 
the rhythm of their L1, it is highly important that they make 
consciously aware of the English system of rhythm. The 
basic unit of English rhythm is the syllable. A syllable is 
most simply explained as something with a vowel sound at 
its center. And while the number of syllables in a word is 
usually obvious to a native speaker of English, learners 
being accustomed to different phonological rules may not 
hear the syllable divisions in the same way. Since this 
seriously affects both intelligibility and listening 
comprehension, time must be spent training students’ ears 
to notice the number of syllables in the words they learn. 
Precisely, Vietnamese rhythmic pattern does not have the 
differences in intensity between stressed and unstressed 
syllables; on the contrary, English rhythmic pattern has 
differences in intensity (of course also in pitch and vowel 
duration). As a result, to be affected by this mother-tongue 
characteristics, Vietnamese students are not aware of the 
importance of syllable weight, shown through intensity, the 
main cue to identify English word stress, which decide the 
ability to catch the accurate information based on the main 
syllable of a word, which is not only the stressed syllable 
but also the tonic syllable in a tone unit. Therefore, teachers 
should spend more time training students how to count the 
number of syllable in a word, identify the syllable weight 
(strong syllable/ heavy syllable = stressed syllable and 
weak syllable/ light syllable = unstressed syllable) to be 
able to follow the English rhythmic pattern. Therefore, 
from the conclusion above, the English stress rules for 
English multi-syllabic words, are systemized, as follows 
[[19]]. 
44 Tran Thi Thanh Dieu: Some English Stress Mistakes and Solutions - A Phonetic Experimental 
Research on Vietnamese Students 
 International Journal of Language and Linguistics 2017; 5(2): 39-49 45 
46 Tran Thi Thanh Dieu: Some English Stress Mistakes and Solutions - A Phonetic Experimental 
Research on Vietnamese Students 
 International Journal of Language and Linguistics 2017; 5(2): 39-49 47 
Figure 6. English stress rules. 
From the table of complicated stress rules above, a brief 
summary of key points for recognizing the places of stress in 
English words has been consolidated based on rhythm, melody, 
word types (simple, compound, complex), word class (N, V, 
Adj), and the number of syllable with or without affix, as well 
as syllable structure based on the Rhythmic patterns [[18]]. The 
foundation of English rhythmic patterns is the existence of the 2 
types of syllables: light syllable and heavy syllable, called 
Trochee: Trochee: Trochaic foot with 1 long syllable (= heavy 
syllable = strong syllable = stressed syllable) and 1 short 
syllable (= light syllable = unstressed syllable). Strong syllable 
is a syllable with initial consonant and a complicated rhyme 
which consists of final consonant and a short vowel or long 
vowel or a diphthong as nuclei [[18], p. 125]. On the contrary, a 
light syllable contains a vowel in the rhyme, with or without 
onset but no coda, as the first syllable in the word report, about 
[[18], p. 85]. 
Therefore, based on the distinction between heavy syllable 
and light syllable, word class, and the number of syllable with 
or without affix, as well as syllable structure based on the 
Rhythmic patterns, the characteristics of stressed and unstressed 
syllable have been simply systemized as follows: [[19], p. 119 – 
124]. 

 The main characteristics of the unstressed syllable: 
Syllable containing schwa or short vowel or diphthong 
/
∪/, ending with not more than 1 consonant. 

 The main characteristics of the stressed syllable: the 
syllable containing long vowel or diphthong or ending 
with more than 1 consonant. 

 Especially, no initial syllable in a verb and no final 
syllable in a noun, as well as no prefix are stressed. 
(i). Simple Words: Multi-syllabic Words Without Affix 
(a). Simple disyllabic words: Syllable containing long vowel 
or diphthong or ending with more than 1 consonant is stressed. 
Ex: photo [’f∪t∪], chorale [k ‘r≙:l], comfort [‘kmft]. 
(b). Simple trisyllabic words, with some special points 

 Trisyllabic verb: No initial syllable is stressed. Therefore, 
syllable containing long vowel or diphthong or ending 
with more than 1 consonant is stressed. Ex: entertain 
/[ent ’tein]. 

 Trisyllabicnoun: No final syllable is stressed. Therefore, 
the syllable containing long vowel or diphthong orending 
with more than 1 consonant is stressed. Ex: character 
[‘k∵r∩kt], mimosa [m∩’m∪s]. 
Figure 7. The main characteristics of the stressed and unstressed syllables in 
simple words. 
48 Tran Thi Thanh Dieu: Some English Stress Mistakes and Solutions - A Phonetic Experimental 
Research on Vietnamese Students 
(ii). Complex Word: Multi-syllabic Word with Affix 
(a). Prefix 

 There is no prefix of one or two syllables that always 
carries primary stress. 

 Stress in the word with prefix is governed by the same 
rules as those for words without prefixes. 

 Word-class pairs: The stress will be placed on the second 
syllable of the verb but on the first syllable of the noun or 
Adjective. 
Figure 8. The stress characteristics of prefix. 
(b). Suffix 

 Suffixes carrying primary stress themselves: (-ain, -ee, 
-eer, -ese, -ette, -esque, -ique). Ex: entertain /ent ’tein/; 

 Suffixes that do not affect stress placement: 
(‘-able’,’-age’,’-al’,’-en’,’-fu’,’-ing’). 

 The stress on the syllable immediately preceding the 
suffix: 
(‘ish’‘-like’,’-less’,’-ly’,‘-ment’.‘-ness’,’-ous’,’-fy’,’-wisw
’,’-y’) 

 Suffixes that influence stress in the stem: (‘-eous’, 
‘-graphy’,’-ial’, ‘-ic’, ’-ion’, ‘-ious’, ’-ty’) 
Figure 9. The stress characteristics of suffix. 
(iii). Compound Word: with 2 Roots 
In the compound with 2 Nouns, The 1st syllable is stressed. 
In the other cases, the 2nd syllable is stressed. 
Figure 10. Characteristics of the stressed syllable in compound words. 
4. Conclusion 
In short, English word stress can be recognized by the 
following criteria: 

 Syllable structure characteristics: Only strong syllables 
are stressed. Strong syllables (sometimes called heavy 
syllable) is a syllable which has a complex rhyme, with 
two cases. First, a heavy syllable may have a short vowel, 
but one or more coda consonants. Second, it may have a 
branching nucleus, consisting of a long vowel or 
diphthong; such a syllable will be heavy whether it also 
has a bled coda; 

 Word structure: Simple words is based on the syllable 
structure characteristics to recognize stress. Complex 
word: no prefix is stressed; Suffixes are stressed and 
unstressed, change stressed syllable or not. Compound 
words with 2 nouns are stressed on the first syllable; 
otherwise, the second syllable is stressed; 

 Rhythmic pattern Stress-timed language, with the 
rhythmic pattern based on the regular repetition of the 
stressed syllables: Pattern {F = [S W]}, (F = Foot, S = 
strong, W = weak); 

 Intensity: English word stress can be mainly recognized 
by intensity; therefore, stressed syllable is pronounced 
with much force, also longer (duration), and higher 
(pitch). 
Remembering the four criteria above helps students prevent 
from the three main types of stress errors: (1). Rhythmic error 
(no Rhythmic Pattern {F = [S W]}); (2). Stress placement 
error; and (3). The combination of Rhythmic and Placement 
error. 
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