1. Full name: Nguyen Thi Huyen                                                

2. Sex: female

3. Date of birth: 21/05/1986                                                       

4. Place of birth: Ha Noi

5. Admission decision number: 2999/QD-XHNV-SDH, Dated 30/12/2013, by VNU President

6. Changes in academic process: None

7. Official thesis title: English Code-switching in Vietnamese Casual Conversations (a case of Vietnamese students of English in universities in Hanoi)

8. Major: Vietnamese Linguistics                                                                       

9. Code: 62 22 01 02

10. Supervisor: Associate Prof. Dr. Trinh Cam Lan

11. Summary of the new findings of the thesis:

Firstly, with the respect to the matrix language frame (MLF), the analysis indicated that Vietnamese is the matrix language (ML) in code-switching utterances in a number of ways and English refers to the embedded language (EL) with a lesser role. Among 964 utterances which collected in 115 conversations we have three model: (1) 321 well-formed constituents entirely in the ML, (2) 163 well-formed constituents entirely in the EL and (3) 480 mixed utterances (ML + EL constituents). 163 well-formed constituents entirely in the EL were classified by structure including Simple sentences (10,4%) and Subjectless sentences (89,6%) and when classified by illocutionary force we have Affirmative (what, why, how…), Negative utterances (10,4%), Directive utterances (6,8%), Interrogative utterances (15,3%), Exclamative utterances (8%). 480 mixed utterance is the central analysis including the matrix language island (ML island), the ML + EL island and the embedded language island (EL island). Due to the purpose of chapter 2, we only analyze (2) and (3). Structurally, most of EL constituents are words, phrases stand number two and sentences are the last. Phonetically, the ML sets the frame of sentences showing code-switching and change the way how to pronounce the EL constituents such as English initials are tonal which taken to the changes in consonants and vowels English system. Major part of speech characteristics of EL (English) including: Noun (70,5%); Verb (20,1%), Adjective (8,5%) and the remain (0,9%).

Secondly, for the motive of code-switching and linguistic behavior, Vietnamese students of English quite "interested in code-switching" which marked code-switching is chosen to convey certain messages of intentionality. Linguistic behavior of Vietnamese students of English is the most unforeseen result. English learning result, time spent learning, English learning hobby or frequency of learning English have negligible effect on their code-switching frequency, meanwhile, all these factors have positive effect on their linguistic behaviors.   

12. Practical applicability: The findings help to clarify some hypothesis models which carried out foreign language communities can be applied satisfactorily to Vietnamese discourse which has English code-switching in casual conversations between Vietnamese students of English in universities in Hanoi.

13. Further research directions: Code-switching between Vietnamese students of English in high school as well as Vietnamese officers who work for foreign companies or foreign invested corporations are likely to be our further research directions.

14. Thesis related publications:

1. Nguyễn Thị Huyền (2016), “Evidence from the matrix language hypothesis: Vietnamese-English code-switching in casual conversations”, Language and Life (9), pp45-53.

2. Nguyễn Thị Huyền (2016), “English code-switching in Vietnamese conversations – From the pragmatics view”, Journal of Foreign Language Studies (48), pp29-41.

3. Nguyễn Thị Huyền (2017), “A study of code-switching motivation of English in Vietnamese communication (a case of code-switching by English major students in universities in Hanoi)”, Lexicography & Encyclopedia (2), pp77-84.