The strategies to develop bilingual ability for Vietnamese

International Journal of Language and Linguistics 
2018; 6(2): 36-50 
doi: 10.11648/j.ijll.20180602.12 
ISSN: 2330-0205 (Print); ISSN: 2330-0221 (Online) 
The Strategies to Develop Bilingual Ability for Vietnamese 
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: 
To cite this article: 
Tran Thi Thanh Dieu. The Strategies to Develop Bilingual Ability for Vietnamese. International Journal of Language and Linguistics. 
Vol. 6, No. 2, 2018, pp. 36-50. doi: 10.11648/j.ijll.20180602.12 
Received: February 11, 2018; Accepted: March 26, 2018; Published: March 30, 2018 
Abstract: The hypothesis is that non-native language speakers (e.g., Vietnamese who study English) face lots of difficulties 
due to the differences in linguistic features and negative transference. Therefore, no one can deny that it is not easy to study a 
language and more difficult to study a second language or a foreign language now that every language in the world has its own 
characteristics which are nearly completely different from one another. To solve this problem, many linguists have created their 
theories of second language acquisition, such as Behaviorist's theory, Nativist's theory, Interactionist's theory, Information 
Processing theory, Vygotsky's theory, Halliday's theory, Sociolinguistic's theory. Therefore, with the hope to solve those 
problems, this study focuses on some difficulties facing learners of English and their solutions. The article is divided into 3 
main parts, including difficulties in the four skills as (1) speaking and listening for communication such as prosody and 
fluency; (2) writing and (3) reading. About the solutions for the difficulties mentioned above, to begin with, in prosody, 
solution focuses on the importance of combining phonological knowledge with rhythm, melody, English stress rules and 
syntax rules in teaching and learning English intonation affected by stress for Vietnamese students, verified by Experimental 
Phonetics. Moreover, writing, grammar and vocabularies improving as well as identification of the types of writing can be 
considered as one of the practical solutions. Last but not least, in reading, K-W-L strategy (K: KNOWN, W: WHAT, L: 
LEARNT), one the best ways to activate schemata is also the suitable solutions as well. 
Keywords: English Rhythmic Patterns, Melody, Phonetic Experiment, Schemata, Interview, Questionnaire 
1. Introduction 
Language is a system of interrelated terms, the underlying 
code which ensures that people can speak and understand 
each other [21]. It has social underpinning and is an operative 
system embedded in brain of everyone who has learnt a given 
language. This system is a network of relationships which 
characterized as being of the two kinds: "syntagmatic" (i.e. 
items are arranged in the consecutive, linear order) and 
associative, later termed "paradigmatic" (i.e. the organization 
of units in a deeper fashion dealing with grammatical and 
semantic relations) [22]. In addition, language is emphasized 
as a system of (arbitrary signs and the central part of overall 
science of sign relations or semiotics (following CS. Peirce's 
terminology). In the other words, language is a system of 
recourse (consisting of first, the simultaneous lexico-
grammar (words and grammar) which has three aspects 
consisting of transitivity (things, even, circumstance, mood 
(structure, elements, theme-rheme, cohesion) and second, the 
generic structure of text) to make the three simultaneous 
meaning (consisting of idealtional-representing experience 
and logic as well as interpersonal-exchanging information 
and goods-and-services, expressing position and textual-
organising the flow of information) in context. Therefore, 
language comprises both form and meaning that must be 
focused on the same level [23]. 
As a result, not only vocabularies but also grammar must 
be paid much attention to when learning a language, 
especially a foreign language. In Vietnam, no foreign 
language is widely used so Vietnamese quite naturally have 
few opportunities to use or to improve a second language 
(but in Vietnam they are all foreign languages), as well as 
they hardly have purpose for learning unless they are in 
special jobs or situations where they have to meet foreigners. 
Therefore, learners of foreign languages in Vietnam face lots 
of difficulties, especially learners of ESP. As a result, the 
time has come when a research should be carried out to find 
 International Journal of Language and Linguistics 2018; 6(2): 36-50 37 
out the difficulties facing Vietnamese learners of foreign 
languages, detailed in the topic “The lecturers and students’ 
ability and method to acquire the foreign languages”, with 
the scope is limited in Vietnam National University HCMC - 
Vietnam, from which “The strategies to develop the bilingual 
ability for Vietnamese in the multi-lingual communicative 
context have been systemized”, as the permission of carrying 
out the research from the University of Social Sciences and 
Humanities – Vietnam National University, written in the 
following decision document: 
Figure 1. Written dicision to allow the research done. 
The topic has been developed through the phonetic 
experimental research into prosody, especially English 
prosody, which has been considered as the most difficult in 
learning English; as well as the survey research through the 
collection of experiences in learning and teaching foreign 
languages, as well as difficulties facing students and 
lecturers, by the questionnaires and questions for 
interviewing lecturers and students in Vietnam National 
University. Moreover, the improvement of lesson plans, the 
solutions for the problems facing learners have been also 
systemized. In the end, some improved teaching methods 
have been raised for consideration. 
However, something that should be mentioned is all the 
questionnaires and interview questions have been created in 
Vietnamese language through Google forms for distance 
investigation, which is suitable for the time and the ways the 
Vietnamese interviewers participate in the survey. Therefore, 
since the research was carried in Vietnamese context, the 
questionnaires have been written in Vietnamese for 
Vietnamese students to answer the questions now that 
bilingual questionnaires or interview questions faces 
something relating to the respected field. As a result, the 
questions written in Vietnamese are the best choice which 
adapts all aspects. 
2. Methodology 
2.1. Pilot Study 
The pilot study of the interview and questionnaire was 
carried out with the lecturrers and students in the Vietnam 
National University. The lecturrers and students who 
participated in the pilot study were also foreign language 
teachers and students at English and non-English 
department. 
The methods used in the stress and intonation research are 
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 as well as 
intonation mistakes and the solutions. The word samples for 
stress research were recorded from the ‘Oxford Advanced 
Learner Dictionary’ ‘Cambridge Advanced Learner 
Dictionary’ and ‘Multi-Dictionary version 9.0 Huy Biên 
2008’, called standard pronunciation (Cách phát âm chuẩn = 
CPAC) or RP (Received pronunciation) and from the 
population (students), called investigating samples (Mẫu 
khảo sát = MKS) or T (Token). In addition, the sentence 
sample for intonation research were recorded from the CD 
ROM of the Cambridge Book for Cambridge Exam - 
Examination paper from University of Cambridge ESOL 
Examination – IELTS 5 - Cambridge University Press, called 
standard pronunciation: RP (Received/ Standard 
pronunciation, called CPAC in Vietnamese) and from the 
population (students), called investigating samples (T 
(Token: investigated samples, called MKS in Vietnamese). 
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). 
2.2. Procedure & Research Schedule 
The questionnaires and Interview questions were sent 
randomly to the lecturers and the students in the Vietnam 
National University via email, Google forms and direct 
interview. The time for the research to be carried out is from 
January 2010 to February 2018 
Table 1. Reaearch Schedule. 
Time What to do (Action) (Step) Findings – Result 
1/2010 – 1/ 
2015 
Research into prosody: 
English prosody to find out intonation mistakes made by 
Vietnamese students 
Comparison between English and Vietnamese prosody to 
find out the solutions for intonation mistakes to improve 
speaking and listening skills 
A case study of solutions to some intonation mistakes made by 
Vietnamese students - A phonetic experimental research. International 
Journal of Language and Linguistics USA – ISSN 2330-0221 – 2015; 3 
(2) 
1/2010 – 1/ 
2015 
Research into second language acquisition 
Summary of second language acquisition theory 
A Some Vietnamese Viewpoints upon Second Language Acquisition 
Theories in Language Contact Environment. International Journal of 
38 Tran Thi Thanh Dieu: The Strategies to Develop Bilingual Ability for Vietnamese 
Time What to do (Action) (Step) Findings – Result 
Vietnamese viewpoints on second language acquisition 
theories 
Language and Linguistics USA – ISSN 2330-0221 – 2015; 5 (2) 
1/2010 – 1/ 
2015 
Research into teaching methodology 
Schemata activating skill 
Trying a suitable strategy (KWL strategy) to teach reading 
comprehension 
Trying K-W-L Strategy on Teaching Reading Comprehension to Passive 
Students in Vietnam. International Journal of Language and Linguistics 
USA – ISSN 2330-0221 – 2016; 1 (2) 
1/2010 – 1/ 
2018 
Research into prosody: 
English prosody to find out stress mistakes made by 
Vietnamese students 
Comparison between English and Vietnamese prosody to 
find out the solutions for stress mistakes to improve 
speaking and listening skills 
1. Some English Stress Mistakes and Solutions – A Phonetic 
Experimental Research on Vietnamese Students, International Journal of 
Language and Linguistics USA – ISSN 2330-0221 – 2017; 3 (2) 
2. Hiện tượng liên ngữ tiếng Anh ở sinh viên người Việt. Tạp chí Tự điển 
học và Bách Khoa Thư – ISSN 1859-3135 – Số 3 (17), tháng 5 - 2012 
3. Phonetic experimental research into the acquisition of English stress 
through rhythm by Vietnamese students. Tạp chí Khoa học Công Nghệ 
Giao thông Vận tải - ĐHGTVT TP.HCM – ISSN 0866-7020 – Số 2-04/ 
2012 
4. Cách xác định trọng âm từ tiếng Anh đối với sinh viên Việt Nam. Tạp 
chí Ngôn ngữ Đời sống - ISSN 0868-3409 – Số 6 - 06/ 2012 
5. Kiểm chứng phương pháp nhận diện vị trí trọng âm từ tiếng Anh bằng 
ngữ âm học thực nghiệm. Tạp chí Đại học Thủ Dầu Một – ISSN 1859-
4433 – Số 02 (5)/2012 
1/2016 – 10/ 
2017 
Research into the lecturers and students’ ability and method 
to acquire the foreign language in Vietnam National 
University HCMC 
Design the questionnaires, interview questions 
Send the Google form links of questionnaires to the lectures 
and students 
Collect the evidence of lecturers and students’ foreign 
language ability 
Data Analysis 
Having conclusion 
10//2016 – 2/ 
2018 
Using all the research results 
To systemize the strategies to develop the bilingual ability 
for Vietnamese in the multi-lingual communicative context. 
Science publication on international journal 
Submitting the article to the International Journal of Language and 
Linguistics – USA 
2.3. Survey Research 
Using the survey research with the function of: 
(1). Opinion survey to uncover the opinion and attitudes of 
the participant about specific issues such as a new teaching 
method used, teaching ways of the lecturer using KWL 
strategy for teaching reading comprehension,  
(2). Evaluation survey to identify the lecturers and students’ 
ability and method to acquire the foreign language in Vietnam 
National University HCMC, from which the strategies to 
develop the bilingual ability for Vietnamese in the multi-
lingual communicative context were systemized.. Therefore, 
the questions were developed to find out what lecturers and 
students think about their teaching and learning program goal 
or objectives of a particular language program as well as about 
its tests, materials, teaching, administration, the difficulties 
facing learners of foreign language, lecturers’ teaching method, 
and learners’ foreign language study experience (2). 
Judgment survey to obtain the view of participants (only 
samples). Students were asked to judge the effectiveness of a 
language program's objectives and materials in terms of how 
useful or difficult they are, how necessary to future language 
use especially to passive students with the purpose of 
encouraging them to be more active in improving foreign 
language skills, as well as how they were to learn. Students 
were simply providing their judgment. 
-Questionnaire (self-administered and group administered 
questionnaire), to collect the lecturers and students' thinking of 
the subjects in their studying program, the ways of teaching, 
learning and testing. This type of survey is so efficient for 
gathering information on a large scale and also questionnaires 
to collect colleagues' opinions after observing the class. 
Self-administered: used questionnaire for this class and 
Group administered questionnaire: used for the other classes. 
Self- administered Questionnaire used by mailing out the 
Google form links and filled out by participants in their own 
home (i.e., they are self-administered to make sure that they 
were not influenced by any factors such as teacher or 
classmate attention, as well as they have enough time for 
careful answers. 
Group administered questionnaire which is administered to 
participants while they are in class or at meeting. This type 
can solve the problem caused by the Self - administered 
Questionnaire: They often have very low return rate and they 
must be completely self explanatory because further 
clarification is not possible. Moreover, by using this type, the 
students were captive audiences and felt obliged to fill out 
the questionnaire (giving a high return rate), as well as 
lecturers could be present to explain any ambiguities as they 
arise and knew exactly what conditions existed when 
questionnaires were filled out. 
Steps in Survey project 
1. Stating the construct. 
2. Specifying survey objectives and research question: 
 International Journal of Language and Linguistics 2018; 6(2): 36-50 39 
Specifying survey objective: to collect the students' 
attitudes  ... e, condition, 
outcome, attitude, linguistic rules. [12] , [14]. Moreover, 
according to the philosophy of the Socio-cultural Theory by 
Vygotsky, Halliday. Human activities and also result are 
defined by purpose. Three features of activity (Activity 
Theory) are Motivation, Action, and Condition: Motivation 
define activity, action decided by condition, learning 
activities, therefore, must be defined by learning goals. As it 
put by Prof. Bùi Khánh Thế, the vice president of Huflit 
University, “motivation plays a very importtan role in 
learning success”. Moreover, learning is cultural 
development from Inter-psychological (between mind) to 
Intra-Psychological (within minds): begins on social level 
before moving onto psychological level. That means when 
studying anything new, the learning process should happen in 
three steps to gain the mediation: From Object-Regulation to 
Other-Regulation to Self-Regulation. Without the Self-
Regulation is like just looking at something without being 
sure that we can see it or not, Self-regulation is a step for 
learners to check themselves by doing on their own with deep 
thinking, the factor leading to cognition. We should base on 
the view: Zone of proximal Development (ZPD) of 
Vygotsky’s philosophy to check the result of learning 
process [12]. 
4. Conclusion 
In brief, the research has been carried out to find out the 
difficulties facing Vietnamese learners of foreign languages, 
detailed in the lecturers and students’ ability and method to 
acquire the foreign languages, with the scope is limited in 
Vietnam National University HCMC, from which the 
strategies to develop the bilingual ability for Vietnamese in 
the multi-lingual communicative context have been 
systemized. 
From data analysis of the research, the lecturers and 
students in Vietnam National University HCMC have good 
ability to acquire the foreign languages to adapt the 
requirement from the University for working and graduating. 
Moreover, some lecturers are good at a foreign language 
enough to go abroad for teaching and researching. Therefore, 
all of them have their all method to acquire their foreign 
languages such as English, French,  However, they also 
face some difficulties in common, from which the suitable 
strategies have been systemized to solve their problems for 
developing the bilingual ability for Vietnamese in the multi-
lingual communicative context, briefly classified as 
difficulties in the four skills: speaking – listening, reading 
and writing, as follows: 
In the field of speaking and listening, based on the 
questionnaire result, the most difficulties facing learners is 
stress level identification, analyzing intonation patterns, 
fluency caused by translating from mother tongue into a 
foreign language. From the phonetic experiment, three types 
of English stress mistakes has been recognized as Rhythmic 
error, Wrong placement of stress and combination of these 
two types; and seven types of intonation mistakes are also 
summarized as rhythmic pattern, tonic syllable identification 
and combination in pair and in set. Therefore, English word 
 International Journal of Language and Linguistics 2018; 6(2): 36-50 49 
stress can be recognized by the following criteria: Syllable 
structure characteristics, Word structure, Rhythmic pattern, 
and Intensity. Moreover, when pronouncing intonation, 
speakers must pay attention to the melody, illustrated by the 
pitch contour based on the intonation rules. In addition, 
thinking in Vietnamese and translating into a foreign 
language such as English in communication is a popular 
mistake that makes the conversation become more slowly. As 
a result, the useful way is practicing thinking in English by 
some techniques illustrated in the findings of this research. 
Moreover, not only intensive but also extensive listening 
practice plays important role in improving listening skill, 
from which listening and note taking is somewhat a vexed 
question. To solve this problem, note-taking outline, the 
ability of remembering, speaking, writing, are very necessary 
for improving listening skills. Therefore, no-one can deny 
that even though speaking and listening are the two separate 
subjects to practice, they are the two relating sides which can 
support each other in improving learners’ ability and gaining 
success in communication. 
In the field of reading comprehension, the difficulties 
facing readers are grammar and vocabularies, in which 
vocabularies makes the reading process slower, as well as the 
problem with guessing the meaning of the words from the 
contexts. Therefore, to guess the meaning from context, 
readers can base on the meaning of vocabulary items that 
surrounds it; the way the word is formed; background 
knowledge of the subject and the situation. As a result, the 
word relation, the structure relation, the part of speech, the 
word form are the important factors leading to successful 
guessing meaning of words based on the contexts. Beside 
that, the most difficulty facing learners of grammar was 
applying the theories to do the exercises, to real life. One of 
the reasons is that students do not remember the grammar 
rules, the theories. Therefore, learning by heart grammar 
structure is also necessary. In addition, when doing the 
reading comprehension, pay much attention to the grammar 
points used in the reading texts to understand grammar used 
in real contexts. From the importance of grammar mentioned 
above, teacher should teach their students a system of 
grammar knowledge enough in comparison with their mother 
tongue to avoid from negative transference mistake, for them 
to practice all the 4 skills before help students to practice any 
skills. As it put by Ms. Lê Ngọc Báu (MA), the French 
Lecturer in the Faculty of French Linguistics and Literature- 
University of Social Sciences and Humanities – VNU, Ms. 
Nguyễn Minh Thúy (MA), the Chinese Lecturer in the 
Faculty of Chinese Linguistics and Literature - University of 
Social Sciences and Humanities – VNU, and Mr. Võ Duy 
Minh (MA), the English Lecturer in the Faculty of English 
Linguistics and Literature - University of Social Sciences and 
Humanities – VNU, that they always improve their lesson 
plan after every semester in comparison with the mother 
tongue, Vietnamese to help students prevent form negative 
tranference mistakes. Beside that, the appropriateness of this 
method has been proved through my 30-year-teaching life, 
and has been applied with a certain success at my Center of 
Foreign language, named Sa Phi Foreign Language Center – 
Sapphire. Ltd, located in Vietnam, 57 Bùi Đình Túy Str, 
Ward 24, Bình Thạnh District. 
In the field of academic writing, the popular problems are 
identifying wrong types of writing, writing ungrammatically, 
writing incoherently and lacking of vocabularies, as well as 
combination of these mistakes. To solve these problems, 
teachers should teach students how to develop a paragraph 
which consists of a topic sentences, some supporting 
sentences such as explanation, statistics, as well as to 
distinguish among the ways to develop a narrative, 
argumentative, cause-effect . paragraphs/ essays. Beside 
that, to have enough words for a piece of writing, students 
should pay attention to the following ways: (1) Accumulating 
vocabularies from the reading texts. (2) Accumulating 
vocabularies from preparing for writing. (3) Accumulating 
vocabularies from preparing for speaking topic. (4) Making 
plan to cumulate vocabularies [17]. 
Last but not least, from the problems and solutions 
mentioned above, an improved teaching method has been 
raised as the K-W-L strategies to activate background 
knowledge before beginning writing or reading the text or 
any fields. K-W-L is a thinking-reading process, with three 
steps: K (What we know), W (What we want to find out, and 
L (What we learned and still need to learn). This procedure 
can help learners to access the knowledge they already have 
about the topic or make it available appropriately so that 
comprehension can occur: 
The last word is that even though this research has not 
been able to cover all the problems facing learners of 
languages, these raised here should be considered as the 
popular and serious that must be solved to help learners be 
successful in studying and using a language, especially when 
it is not a mother tongue. Therefore, the research is always 
opened for adding new recognition of mistakes made by 
learners and their solutions, as well as any experiences from 
learners and teachers of languages. 
References 
[1] Anderson, John M.; and Ewen, Colin J. (1987). Principles of 
dependency phonology. Cambridge University Press. 
[2] Aoyama, K. & S. Guion. (2007). Prosody in second language 
acquisition. Acoustic analyses of duration and FO range. In 
O.-S. Bohn & M. Munro, eds. Language experience in second 
language speech learning. In honor of James Emil Flege, John 
Benjamins: 281–297. 
[3] Bolinger, D. (1985). Intonation and Its Parts, Melody in 
Spoken English. Standford University Press. 
[4] Brentari, Diane. (1998). A prosodic model of sign language 
phonology. Cambridge, MA: MIT Press. 
[5] Nguyễn Tài Cẩn. (1997). Giáo trình lịch sử ngữ âm tiếng Việt. 
Nxb Giáo dục. 
[6] Chomsky N and Halle M. (1968). The sound pattern of 
English. New York: Harper & Row. 
50 Tran Thi Thanh Dieu: The Strategies to Develop Bilingual Ability for Vietnamese 
[7] Clements, George N. (1985). The geometry of phonological 
features. Phonology Yearbook, 2, 225-252. 
[8] Clements, George N.; and Samuel J. Keyser. (1983). CV 
phonology: A generative theory of the syllable. Linguistic 
inquiry monographs (No. 9). Cambridge, MA: MIT Press. 
ISBN 0-262-53047-3 ISBN 0-262-03098-5. 
[9] De Lacy, Paul, The Cambridge Handbook of Phonology. 
Cambridge University Press. ISBN 0-521-84879-2 (hbk), 2007. 
[10] Trần Thị Thanh Diệu. (2015). A case study of solutions to 
some intonation mistakes made by Vietnamese students A 
phonetics experimental research. International Journal of 
Language. Vol. 3, No. 2, 2015. pp. 52-60. ISSN: 2330-0221. 
[11] Trần Thị Thanh Diệu. (2017). Some stress mistakes and 
solutions, a phonetic experimental research on Vietnamese 
students. International Journal of Language. Vol. 3, No. 2, 
2017. pp. 52-60. ISSN: 2330-0221. 
[12] Trần Thị Thanh Diệu. (2015). A Some Vietnamese Viewpoints 
upon Second Language Acquistion Theories in Language 
Contact Environment. International Journal of Language and 
Linguistics USA ISSN 2330-0221 2015; 5 (2). 
[13] Trần Thị Thanh Diệu. (2016). Trying K-W-L Strategy on 
Teaching Reading Comprehension to Passive Students in 
Vietnam. International Journal of Language and Linguistics 
USA ISSN 2330-0221 2016; 1 (2). 
[14] Trần Thị Thanh Diệu. (2012). Hiện tượng liên ngữ tiếng Anh 
ở sinh viên người Việt. Tạp chí Tự điển học và Bách Khoa 
Thư – ISSN 1859-3135 – Số 3 (17), tháng 5 - 2012 
[15] Trần Thị Thanh Diệu. (2012). Phonetic experimental research 
into the acquisition of English stress through rhythm by 
Vietnamese students. Tạp chí Khoa học Công Nghệ Giao 
thông Vận tải - ĐHGTVT TP.HCM – ISSN 0866-7020 – Số 2-
04/ 2012 
[16] Trần Thị Thanh Diệu. (2012). Cách xác định trọng âm từ 
tiếng Anh đối với sinh viên Việt Nam. Tạp chí Ngôn ngữ Đời 
sống - ISSN 0868-3409 – Số 6 - 06/ 2012 
[17] Trần Thị Thanh Diệu. (2017). English – Japanese language 
and literature, some relation. LAP LAMBERT Academic 
Publishing - ISBN-10 3330344520. ISBN-13 978-
3330344525 – July 5th 2017 
[18] Dornyei, Z. (2003). Questionnaires in Second Language 
Research. IEA. 
[19] Duff, P, A. (2007). Case Study Research in Applied 
Linguistics. IEA. 
[20] Nguyễn Công Đức, Nguyễn Hữu Chương. (2004). Từ vựng 
tiếng Việt. Tủ sách Đại học Khoa học Xã hội và Nhân văn. 
[21] Fromkin V, Roadman, Collins & Blairs. An Introduction to 
Language. Second Australian Edition, 1990. 
[22] Fromkin V, Roadman R, Hyams N. An Introduction to 
Language. Nineth American Edition: Wadsworth Cengage 
learning, Canada, 2011. 
[23] Fromkin V, Roadman R, Hyams N. An Introduction to 
Language. Seventh American Edition, 2003. 
[24] Fry D. B. (1955). Duration and intensity as physical 
correlates of linguistic stress. J. Acoust. Soc. Am. 27, 765–
768. doi: 10.1121/1.1908022. 
[25] Fry D. B. (1958). Experiments in the perception of stress. 
Lang Speech 1, 126–152. 
[26] Fry D. B. (1965). The dependence of stress judgments on 
vowel formant structure. in Proceedings of the 5th 
International Congress of Phonetics Sciences, eds. Zwerner 
X., and Bethge W., Karger: Basel, pp. 306–311. 
[27] Nguyễn Thiện Giáp. (2009). Các phương pháp nghiên cứu 
ngôn ngữ. Nxb Giáo dục. 
[28] Goldsmith, John A. (1995). “Phonological Theory” in John 
A. Goldsmith. The Handbook of Phonological Theory. 
Blackwell Handbooks in Linguistics. Blackwell Publishers. 
[29] Goldsmith, John A. (1979). The aims of autosegmental 
phonology. In D. A. Dinnsen (Ed.), Current approaches to 
phonological theory. Bloomington: Indiana University Press. 
[30] Griffee D. T. & Nunan D. (1997). Classroom Teachers and 
Classroom research. Tokyo, Japan: The Japan Association for 
Language Teaching. 
[31] Hadley G. (2003). Action Research in Action. Singapore: 
SEAMEO Regional Language Center. 
[32] Cao Xuân Hạo. (2006). Tiếng Việt, mấy vấn đề Ngữ âm, Ngữ 
pháp, Ngữ nghĩa. Nxb Khoa học Xã hội. 
[33] Hatch E and Lazaraton A, University of California. (1991). 
The Research Manual Design and Statistics for Applied 
Linguistics. Boston: Heinle & Heinle Publishers A Division of 
Wadsworth, Inc Boston, Massachusetts 02116. 
[34] Nguyễn Quang Hồng. (2002). Âm tiết và loại hình ngôn ngữ. 
Nxb Đại học Quốc gia Hà Nội. 
[35] Jones D. (2002). The pronunciation of English. Cambridge 
University Press. 
[36] Ladefoged, Peter. (2001). A Course in Phonetics (4th ed.). 
Boston: Heinle & Heinle, Thomson Learning. 
[37] McMahon A. (1988). An Introduction to English Phonology. 
Edinburgh Univiersity Press. 
[38] Plonsky, L. (2015). Advancing Quantitative Methods in 
Second Language Research. Roughlet, Newyork and London. 
[39] Richards, R, C. (1973). Error Analysis – Perspectives on 
Second Language acquisition. Longman. 
[40] Roach, P. (1998). English Phonetics and Phonology. The 
Youth Press, Vietnam. 
[41] SEAMEO Regional Language Center. (2003). Research 
Methodology Singapore: SEAMEO Regional Language Center. 
[42] Spencer, A. (1991). Morphological Theory. Cambridge 
University Press. 
[43] Stump, G, T. (2001). Inflectional Morphology – A theory of 
Paradigm Structure. Cambridge University Press. 
[44] Lê Quang Thiêm. (2004). Nghiên cứu đối chiếu các ngôn ngữ. 
Nxb Đại học Quốc gia Hà Nội. 
[45] Đinh Lê Thư, Nguyễn Văn Huệ. (1998). Cơ cấu ngữ âm tiếng 
Việt. Nxb Giáo dục. 
[46] Đòan Thiện Thuật. (1980). Ngữ âm tiếng Việt. Nxb Đại học và 
Trung học chuyên nghiệp.