Attributes of effective EFL teachers in Vietnamese context as perceived by students and teachers

Identifying characteristics of effective teachers has always been a topic of paramount importance. Accordingly, an extensive volume of theoretical endeavours and empirical research has been devoted to the investigation of typical attributes that effective teachers possess in diverse contexts. Yet, current understanding of the issue in Vietnamese setting remains limited. Given that perceptions about effective teachers’ qualities have been typically found to be highly context-bounded, gaining an insight into these attributes in this under-researched context is expected to provide a solid foundation for further attempts to improve the quality of teaching and learning. The present study responds to this pressing need by exploring the perceptions held by 200 learners and 22 teachers in a language school in Vietnam, employing questionnaires for collecting both quantitative and qualitative data. A theoretical framework adapted from Shulman’s (1986, 1987) model of teachers’ knowledge base was employed. Findings from the study revealed both convergence and mismatches in the perceptions held by the teacher and learner groups. As a whole, teachers, and learners convergently prioritised teachers’ subject matter content knowledge as most important, compared to pedagogical content knowledge and teachers’ identity and interactions with learners. Both groups also voted teachers’ ability to provide clear instructions and explanations as the most important pedagogical feature of effective teachers and uniformly downplayed the role of sociocultural knowledge and the ability to effectively use technology. More in-depth analyses, however, showed that teachers placed more importance over the pedagogical aspects of subject matter knowledge, language proficiency, and teaching methodology, whereas learners more appreciated the psychological and motivational aspects. In particular, the teacher participants highly valued the teachers’ ability of classroom management, material adaptation, and facilitating students’ engagement in learning activities. In contrast, qualities most desired by learners included a positive attitude towards the teaching career and teachers’ willingness to care, understand learners’ problems, encourage, and treat all students on a fair basis.


INTRODUCTION
The question of what makes effective teaching has always been a central tenet in any education system worldwide. Although answers to this question can context, insights into what students define as effective teaching establishes a firm foundation for teachers' improvement of learners' outcomes if teachers are well aware of what students expect from them and appropriately respond to the expectations (Barnes & Lock, 2010). Insufficient attention to learners' beliefs and needs, as Hortwitz (1987) warns, might lead to their loss of confidence in the teachers' ability and the instructional approach. Without such confidence, learners' motivation could be significantly deficient, which might, in turn, undermine the effectiveness of the learning process and the achievement of the intended learning outcomes (Dörnyei, 2001;Horwitz, 1987).
Warnings have also been raised about the negative impact on students' learning outcomes if mismatches exist between learners' and teachers' perceptions of effective teachers and teaching. Such mismatches of perspectives might negatively affect students' satisfaction in their learning (Horwitz, 1987;Schulz, 1996). Evidence from research that explores learners' and teachers' beliefs in teaching and learning (e.g., Nguyen, 2018;Tran, 2015) has also proved that perceptions are often highly context-bound. In this sense, gaining an insightful understanding of what students in a particular context perceive as crucial qualities of effective teachers can be seen as crucial for informing the tasks of preparing pre-service teachers as well as supporting in-service teachers to enable them to best implement or adjust their current teaching practices.
Despite a large volume of studies investigating learners' perceptions of effective teachers in various contexts (e.g., Barnes & Lock, 2010, 2013Brosh, 1996;Kember & Wong, 2000;Park & Lee, 2006), there has been a dearth of research focusing on this particular topic in Vietnamese setting until recently. Provided the well-established significance and contributions of findings from previous studies in this research strand, it has been long overdue for an in-depth investigation into what Vietnamese EFL learners perceive as effective teachers and the extent their perceptions converge with their teachers' beliefs. The present study responds to this urgent need by examining perceptions about effective teachers held by learners and teachers in a Vietnamese language school context. In particular, it aims to quest for answers for the following research questions: (1) What qualities do Vietnamese learners perceive as important for effective EFL teachers? (2) Are there any differences in the perceptions held by different groups of learners? (3) To what extent do students' perceptions converge with those held by their teachers?

REVIEW OF LITERATURE
A review of empirical studies investigating qualities of effective teachers shows that those previously conducted studies mainly fall into two main streams: (1) learners' or teachers' perspectives on effective teachers; and (2) convergence/ divergence of teachers' and learners' perceptions on the issue. Together, findings from these studies shed critical light on what makes effective teachers in diverse contexts.
To begin with, a large volume of studies centred on learners' perspectives in various settings reaffirms the role of teachers' subject matter content knowledge (henceforth SMCK), language competence and pedagogical content knowledge (henceforth PCK) as crucial aspects of effective teachers. For example, in a study with 200 teachers and 406 students in Israel, Brosh (1996) reported that teachers' competence in English use and their PCK were rated as most significant although the former was more highly valued. In Korea, two studies conducted by Barnes and Lock (2013) with 222 university students, and Park and Lee (2006) with 399 high school students both showed that PCK or teachers' delivery ability was rated more highly than their knowledge of English and competence. In an Indian context, Clement and Rencewigg (2020) found from a study of 124 college students that the participants viewed teachers' methods of teaching and subject knowledge as the two most important aspects together with superior communication skills. In Turkey, an investigation into 93 Turkish learners' perceptions of effective teachers conducted by Hismanoglu (2019) using both questionnaire and interviews, it was found that a good level of linguistic knowledge and pedagogical knowledge were highly appreciated by students besides other personal personality traits.
In the same context of Turkey, Toraman (2019) explored effective teacher characteristics from multiple perspectives, getting involved four groups of participants -402 public school pupils, 139 teachers, 207 prospective teachers and 19 teacher education experts. Findings from the study revealed that teachers' competence in SMCK and teaching skills were ranked among most crucial qualities alongside teachers' personal characteristics and professional development. In a different setting of Kuwait, a study carried out by AlFadley et al. (2020) exploring 487 elementary female teachers' perceptions of effective teachers reported that teachers' language proficiency, their familiarity with the English culture, awareness of current teaching techniques, the ability to select appropriate materials, and knowledge of how to evaluate students were ranked as topmost important. As a whole, findings from these studies highlighted the critical role that teachers' PCK and SMCK play. There appears, however, to be no consensus or consistent conclusions concerning which of these is more important across these studies.
Other studies from the same research strand, however, appear to highlight the importance of teachers' personality and relationships or interactions with learners as crucial characteristics of effective teachers. For instance, Chen and Lin (2009), in a study with 198 junior high school students in Tainan, China found that the most desired characteristics included enthusiasm, friendliness, open-mindedness, respect and care for students. To a great extent, these qualities resonate with what Pennington (1990) earlier proposed as "attitudes". Teachers' personal attributes were also reported in Koç's (2013) study of 365 Turkish learners in three levels of elementary, secondary and high school. Effective teachers, as defined by participants in this study as being patient, kind, and taking attention of students in the classroom, participating in activities with them and treating them on a fair basis. These qualities were further justified as key qualities that enabled teachers to effectively motivate students, maintain good classroom discipline, create an entertaining learning environment, understand learners' needs and establish good relations with them. In another study conducted by Hismanoglu (2019) of Turkish students' perceptions, it was also found that the most desired personal attributes students had towards their teachers comprised being enthusiastic and lively, having interest in their teaching and a sense of responsibility.
In Thailand, Chen (2012) reported that her participants (60 university students) linked effective teachers with five personal traits including emotion (patient, humorous, enthusiastic), kindness (friendly, polite), fairness, lenience and responsibility. In a similar vein, Charles's (2019) study of four teacher participants in two American high schools using qualitative methods of interviews and observations pointed out three major groups of effective teachers' attributes including innate traits, individual skills and relationship-based features. These groups were further specified to include typical attributes of being approachable, commitment, compassion, flexibility, empathy, perseverance, respect and willingness to talk to students. In Iran, Yazdanipour and Fakharzadeh's (2020) exploration of characteristics of effective language teachers from the perspective of 27 school administrators further highlighted these stakeholders' prioritisation on seven key themes of teachers' appearance, personal traits, business-related traits, love of the profession, professional competence, work experience and interpersonal relationship. Interestingly, from these administrators' viewpoint, teachers' appearance and personal traits appeared to play an even more important role than professional aspects. As evident in these research findings, teachers' personal attributes and the way they interact with students have been firmly established as a crucial dimension that effective teachers in various contexts demonstrate.
Results from the second research strandstudies exploring convergence of learners' and teachers' perceptions of effective teachers -further reinforce the importance of the teachers' attributes identified by studies in the first research stream. Findings from this research stream also inform mixed degrees of convergence of the perceptions held by teachers and learners. For instance, in Brosh's (1996) study, both teachers and students highly valued teachers' PCK, specified as the ability to transmit knowledge in a way that is easy to understand and remember. Both groups also underrated the importance of socio-cultural knowledge in language learning. However, while learners in this study highly appreciated teachers' availability for support after class and fair treatment to all students, their teachers gave more credits to teachers' ability to organize, explain and clarify ideas. In Iran, Ramazani's (2014) study of 121 teachers and 384 university students reported that teachers ranked English proficiency as the most important whereas students perceived PCK as of highest significance. In the same context, Moradi and Sabeti (2014) explored 34 teachers' and 122 students' perceptions of the importance of five categories of SMCK, PCK, communication skills, managing skills and teaching experiences. Results showed that both groups voted PCK as the most important feature. The divergence, however, lied in the fact that while teachers held a professional view with more concern over their knowledge and expertise on theories and methodology, learners viewed it from a more realistic angle, and expected teachers to be able to personalize their teaching to students' lives, concerns and interests. In a more recently conducted study of 45 Slovak EFL students and 32 teachers, Tarajová and Metruk (2020) found that students gave more weight to the teachers' personality traits and the way the teachers behaved to students in conjunction with language expertise. Divergent from this, teachers leaned more towards pedagogical skills and knowledge of teaching methodology.
In Vietnamese context, Tran's (2015) study was found to be the key endeavour that shed light on students' expectations of effective English teachers. Preliminary qualitative data gathered from interviews with groups and individual students in phase 1 of the study informed a list of twelve attributes that Vietnamese learners desired from effective teachers including (1) English competence, (2) knowledge of subject area content, (3) knowledge of cultures of English speaking countries, (4) knowledge of Vietnamese culture, (5) ability to apply EFL teaching principles, (6) ability to meet students' learning needs, (7) ability to exploit teaching materials effectively, (8) ability to manage class effectively, (9) ability to use effective assessment, (10) ability to apply information technologies into teaching, (11) professional attributes and (12) personal characteristics. On the basis of these qualifications, in phase 2, a questionnaire was constructed and administered to 339 English learners across nine cities in the south of Vietnam to further explore the learners' definitions of effective English teachers in this particular context. Results from the study indicated that teachers' English competence and their ability to apply EFL teaching principles and classroom management skills were ranked as two most important qualities while teachers' ability to apply information technology (IT) into teaching and professional attributes were rated as the least important. It was also found that while learners' genders, levels of education and disciplines did not significantly affect students' perceptions of teachers' qualities, their geographic distribution (living in cities or countryside), levels of English, study lengths and types of institutions they attended did have an impact. It was concluded by the study that there could be no single set of qualities of teachers that fitted all groups of learners in every context, and that teachers in Vietnam needed to pay closer attention to the expectations held by each individual learner group.
The above review of literature highlights three critical facts about research into the qualities of effective teachers. First, it establishes a list of five most commonly identified characteristics for effective teachers across contexts including (1) teachers' English competence; (2) teachers' SMCK; (3) PCK; (4) personal traits and characters, and (5) teachers' interactions and relationships with students. Second, it underlines the multifaceted nature of teachers' characteristics, which are perceived and constructed differently by different groups of learners and teachers in specific sociocultural contexts. Third, although these previously conducted studies, to some extent, reported on similar general categories of teachers' qualities, knowledge and skills required for effective teaching implementation, there appeared to be no clear consensus when specific sub-components of these general categories are examined. To a great extent, this lack of agreement further presses on the urge for an in-depth investigation that sheds more light on the issue from the viewpoint of both teachers and learners of various levels and programs in contexts where such an understanding is still modest such as Vietnam.

Theoretical Foundations of Teachers' Knowledge Base for Effective Teaching
A plethora of theoretical models (e.g., Dewey, 1904;Elbaz, 1983;Shulman, 1986Shulman, , 1987) that conceptualise crucial aspects of the knowledge base that teachers rely on in teaching enactment has been proposed. Among these, Shulman's model has been commonly viewed as a comprehensive framework for categorising components of teachers' knowledge base with a fine-grained list of seven knowledge groups that classroom practitioners need to wellequip, namely knowledge of curriculum, learners, context, educational ends, values and purpose, SMCK, general pedagogy and PCK. Most significant in the model is the concept of PCK, defined as "the special amalgam of subject matter and pedagogical knowledge that distinguishes teachers' knowledge of that held by other subject specialists" (Shulman, 1987, p.8).
These well-established models of teachers' knowledge base in general education paved the way for the construction of frameworks of language teachers' knowledge base. Although language teaching does require, to a large extent, similar expertise, attributes and skills that teachers of any other subject matters need, becoming a teacher of language is considered to be quite a unique process since the content and the process of learning are the same (Bernhardt, 1987). In other words, as "the medium is also the message in language teaching" (Bernhardt, 1987, p. 305), attempts to improve language teacher education need to take into account this uniqueness. Advocating this standpoint, Borg (2006), in exploring the distinctiveness between foreign language (FL) teachers from teachers of other subjects, found that FL teachers are mainly differentiated from other subject teachers on the basis of the nature of the subject, the content of teaching, teaching methodology, teachers' characteristics and their relationships with students. In light of these findings, Borg (2006) concluded that FL teachers' distinctiveness was a socially constructed phenomenon that may be defined in various ways in different contexts. He further suggested that future research focusing on this particular issue be grounded in specific language teaching settings.
Numerous conceptualisations of language teachers' qualities concertedly inform a multiplicity of typical attributes that describe effective teachers. In particular, Pennington (1990) proposes an extensive list of attitudes (including love for English, persistent urge to upgrade oneself, readiness to go extra mile, a feeling of excitement about one's work, flexibility and openness to change), interpersonal skills, confidence, practical experience, knowledge of theoretical foundations of language learning and teaching techniques, and awareness of alternative teaching techniques as most important attributes of effective teachers. Pennington (1990) further highlights the importance of teachers' informed knowledge of themselves as teachers and their skills for assessing different teaching contexts and classroom conditions. Many of these attributes are also featured in Harmer's (1998) definition of effective teachers, in which he further emphasizes teachers' knowledge, personality and ability to make lessons interesting and entertaining to students. In a more detailed model, Brown (2015) lists thirty features of effective teachers and groups them into four main categories including technical knowledge, pedagogical skills, interpersonal skills and personal qualities. In its simplest sense, technical knowledge refers to teachers' competence and knowledge of the language taught and insights into the language learning process. The second group, pedagogical skills, has its reference to the teachers' ability to effectively plan, design and execute lessons. This group, in turn, entails an extensive number of classroom techniques, approaches and skills that teachers resort to in instruction. Finally, interpersonal skills are relevant to the manner of teachers' classroom interactions while personal attributes reflect their own morality and characteristics. In one of the most recent revisiting of the topic of the teachers' qualities in a changing world, Renandya and Jacobs (2021) suggest teachers' language proficiency, pedagogical knowledge and skills and understanding of their students as the top three most crucial attributes among the nine aspects that teachers in the Covid-19 time need to feature.
As a whole, these seeding categories establish a solid foundation for empirical research that investigates characteristics of effective teachers. In the present study, a theoretical framework adapted from Shulman's (1986Shulman's ( , 1987 model was adopted. Even though Shulman's model was among seminal frameworks for conceptualising teachers' knowledge base, it remains one of the most holistic models thanks to its fine-grained and clearly defined list of teacher knowledge components. Accordingly, the adjusted model encompasses three overarching groups of teachers' qualities and knowledge. In particular, the first group -SMCK entails three specific components of teachers' English competence, knowledge of the English language, and socio-cultural aspects of English-speaking countries. The second category, PCK, houses within itself six subsets: teachers' general understanding of the curriculum, knowledge of teaching methods, knowledge of strategies, techniques, and skills in lesson enactment, understanding and use of teaching materials, evaluation and feedback techniques, and knowledge of language testing. The third component teachers' identity and interactions covers four constituents namely teachers' physical features, educational background, attitude towards teaching and their interactions and relationships with students. The four subsets included in this component are grounded on the basis of the review of literature relevant to the researched setting and the researcher' observations of students' common expectations in Vietnamese context. This adapted framework provides a lens for the investigation of the learners' and teachers' perceptions of effective teachers' attributes and a foundation for the development of the questionnaire in the study.

METHOD
The study employed a mixed-method approach with both quantitative and qualitative data collected. Two instruments were used for collecting data: a questionnaire for learners (Appendix 1 -English version) and a survey for teachers (Appendix 2). The questionnaire for learners was developed on the basis of the aforementioned adapted theoretical model proposed by Shulman (1986Shulman ( , 1987 with 50 Likert-scale type questions administered to 200 student participants. In accordance with the components in the theoretical framework, these 50 questions were divided into three groups of teachers' knowledge of SMCK (6 questions), PCK (20 questions) and teachers' identity and interactions (24 questions which include 4 subcategories of physical features (3 questions), educational and career background (4 questions), attitudes towards the teaching career (4 questions), knowledge of learners (3 questions) and personal attributes and interactions with learners (10 questions)).
The questionnaire items were written in both Vietnamese and English to ensure learners' accurate understanding of the questions. Table 1 below summarizes the three main categories of teachers' knowledge base, the sub-components each category encompasses and specific question items devoted to each specific knowledge subset. For data analysis, data was input into SPSS (version 26) and analyzed in descriptive statistics to get the mean scores, maximum scores, and minimum scores of each cluster.
In terms of participants, 200 Vietnamese EFL learners and 22 teachers in a private language school in the Mekong Delta Region, Vietnam got involved in the study. This particular school was selected for two main reasons. First, this private language school is seen as among the largest and most prestigious language teaching institution in the whole Mekong Delta Region. Second, it was also the institution where the researcher had been working as a teacher and a manager for over ten years; thus it was convenient for him to gain access to both the teachers and learners at the school. At the time of study, these students were attending three English programs: IELTS Preparation (n=51); General English (n=42) and English for Teenagers (n=107). In terms of ages, the first two cohorts of students (IELTS and General English Programs) include mainly university students, aged 18 and above, who attended these English classes as separate from their mainstream programs at the university. The remaining group of teenagers, however, consists of adolescent learners with ages ranging from 11 to 17 with levels varied from pre-intermediate to advanced. The involvement of the teenage learners in the study was seen as having significant practical values since teaching this particular group of learners had been constantly perceived as most challenging in this context. As for the teacher participants, all 22 respondents were selected on the basis that they must be those who were teaching the learner participant groups and were willing to participate in the study.

FINDINGS AND DISCUSSION
This section presents key findings from the study organised into three main parts. First, the learner participants' perceptions of important qualities of effective EFL teachers as informed by the questionnaire will be reported, followed by a presentation on the main differences in perceptions held by the three learner groups: IELTS Preparation, General English, and Adolescent learners. In the last section, the teacher participants' perspective of effective EFL teachers will be presented in comparison with that of the learners.

Students' Perceptions of Effective EFL Teachers
As for the first research question that aims to shed light on the learners' perceptions of effective EFL teachers in Vietnamese context, findings were drawn from the analysis of quantitative data gathered through the questionnaire. To begin with, with respect to the learners' rating of the importance of the three overarching categories of teachers' qualities, as depicted in Table 2, SMCK was ranked most important (m=4.2), followed by PCK (m=3.8) and teachers' identity and interactions (m= 3.7). However, further in-depth analyses with subcomponents of these three main categories revealed three noticeable findings. First, although the group of teachers' identity and interactions, in general, was rated as least important, some of its subsets were most highly valued among all specific qualities. For instance, as presented in Table 3, the sub-group of teachers' attitudes (items 9, 19, 34, 48) was ranked highest among all sub-groups (m= 4.4), a rate higher than that of the subject matter content knowledge group as a whole. Also, the two subsets of knowledge of learners (items 27, 44 and 46) and knowledge of teachers' personal attributes and interactions with learners (items 18, 20, 22, 23, 24, 25, 37, 47, 49, 50) were both equally rated more highly than that of PCK (m=4.0, compared to 3.8). Further investigations into this subset revealed that three most important qualities that learners desired from the teachers were enthusiasm and friendliness, readiness to respond to learners' questions, and fair treatment to students. The last two constituents of this group -teachers' physical features and background, were considered the least important with their means at 2.9 and 3.1, respectively.
With regards to sub-components in the SMCK category, teachers' knowledge of vocabulary was rated as most important (m=4.6), closely followed by knowledge of grammar (m=4.5). Teachers' ability to use language competently both inside and outside classrooms was also rather highly valued with the mean score at 4.4. Teachers' knowledge of society and culture of English-speaking countries and the possession of a native-like accent were ranked least important with the means at 3.6 and 3.7, respectively. Taking the constituents of PCK into consideration, learners most highly valued teachers' ability to provide clear instructions and explanations (item 17; m=4.5). The next highly rated five characteristics with the same mean score at 4.1 included (1) teachers' understanding of the relationship between their teaching content and that in other subjects, (2) teachers' effort in establishing achievable goals for learners, (3) ability to simplify their language use so that learners can follow and understand, (4) their ability to organize activities closely connected to real-life communication situations and (5) ability to supplement suitable material from outside the textbooks. In contrast, students underrated the teachers' ability to speak English 100% in class (m=3.2) and their strict alignment with the prescribed textbooks content (m=2.6). It should also be noted that some of the teachers' pedagogical aspects that can be seen as directly impacting their ability to deliver effective lessons including the ability to organize pair/ group activities and games (items 32, 33), classroom management skills (item 26), ability to provide encouraging feedback (items 21, 40, 41, 42), and ability to apply information technology in teaching (item 30) were also rated relatively low by the learners with their means ranging from 3.3 to 3.9.

Differences in Learners' Perceptions from the Three Groups
Analyses with a focus on the perceptions held by the three specific groups of learners showed that, in general, no significant differences among the groups were found in relation to their rankings for the three main categories of SMCK, PCK and teachers' identity and interactions. As evident in Table 4, although certain variations were found among the learner groups in terms of their ratings for each quality category, as a whole, all three groups of participants rated subject matter content knowledge as most important. However, there appeared to be a slight discrepancy among the groups for their rankings of the other two quality categories. In particular, PCK was only ranked as more important than teachers' identity and interactions by the IELTS group while it was the opposite way around that was found for the two groups of General English and Teenager learners. Further investigations into differences among the groups in relation to their ranking for specific subsets of teachers' knowledge and qualities revealed three important issues that are worth noting. First, as can be seen in Figure 1, for teenage learners there was a higher expectation for teachers to care about their problems in learning (m=4.2 compared to 3.6 (General) and 3.9 (IELTS) as well as the teachers' ability to maintain classroom discipline (m=3.9, compared to 3.5 (General) and 3.1 (IELTS). Second, the IELTS learners displayed a higher expectation of the teachers' competence, knowledge and educational background levels. In particular, among the three groups, the IELTS learners most highly rated the three aspects of teachers' possession of a native-like accent (m=4.0, compared to 3.6 (General) and 3.5 (Teenagers), teachers' ownership of an English-majored qualification or degree (m=4.0, compared to 3.6 (General) and 3.8 (Teenagers) and teacher's good socio-cultural knowledge of English-speaking countries (m=3.7, compared to 3.6 (General) and 3.4 (Teenagers). Finally, learners from the General Program underrated the importance of teachers' trust in learners' ability and efforts (question 22: m=3.7, compared to 4.3 (IELTS) and 4.2 (Teenagers). In addition, although this cohort of learners valued teachers' respect and fair treatment to all students (m=4.3), this rate appeared to be much lower than that of the IELTS Group (m=4.7) and the Teenagers (m=4.6).

Teachers' Perceptions of Effective Teachers
As aforementioned, the third main goal of the study was to explore the extent of convergence between learners' and teachers' perceptions of effective teachers. Accordingly, data related to the teachers' beliefs were collected through a survey with 6 ranking questions and one open-ended question aiming to collect qualitative evidence. As such, findings in relation to the teachers' perceptions are presented in this section will be in direct comparison with the learners' perceptions displayed previously, with the main focus on aspects of clear convergence and divergence.
Overall, evidence from the teachers' rating of the three overarching categories of qualities for effective teachers indicated a high level of converge with the learners' ranking. In particular, analyses of data from question 2 showed that 50% of the teachers (n=11) voted SMCK as the most important while 32% (n=7) opted for PCK as most crucial, leaving only 18% (n=4) rating teachers' identity and interactions with learners as most essential qualities. These rankings feature a high extent of matching with the learners' rating as discussed earlier. More in-depth analyses of the teachers' rating for specific subsets of these three overarching categories, however, revealed both convergence and divergence. For instance, both groups shared a belief that the teachers' educational backgrounds and physical appearance were the least important among all qualities. Both teachers and students also placed a relatively high importance on the teachers' interactions with learners as among top three most important qualities. However, divergence was found in that while learners ranked teachers' attitudes towards the teaching career as topmost important, followed by the teachers' language knowledge and competence. The teacher participants, in contrast, appeared to downplay the significance of teachers' attitudes towards the teaching career which was ranked fourth in the list.
In a similar vein, both convergence and divergence were evident when teachers and learners' ratings of individual aspects of qualities, knowledge and skills are unpacked. For instance, with respect to the SMCK, learners voted for teachers' knowledge of vocabulary and grammar as the two most important, higher than the rank they rated for the competence to use English inside and outside the classrooms. In contrast, the teacher participants viewed the ability to use English for communication competently as the most crucial, followed by their knowledge of vocabulary. The importance of grammar knowledge appeared to be downplayed by the teachers, ranked fifth in the list. Interestingly, in complete alignment with the learners' ranking, the teacher groups also considered socio-cultural knowledge of English-speaking countries as the least important among all the aspects of subject matter content knowledge.
Concerning the individual aspects of PCK, both groups highly rated the teachers' ability to give clear instructions and explanations as well as the ability to organise life-like communicative activities in the classrooms among top three most important qualities. One important mismatch between the two groups, however, was evident in the fact that while learners rated teachers' ability to evaluate and give encouraging feedback as the second most important quality within the PCK category, teachers placed this ability at seventh position, after classroom management skills and ability to adapt materials in an appropriate manner. With respect to the final group of teachers' identity and interactions, convergence was found with two out of the three most important attributes. In specific, both teachers and students gave credits to (1) teachers' personality of friendliness, caring and fairness in treatment, and (2) teachers' willingness to respond students' questions. Evidence of convergence in perceptions of the two groups was also present in the fact that they both highly valued teachers' possession of a clear voice, a passionate and enthusiastic manner toward the teaching career and teachers' constant efforts in improving their professional knowledge and skills. Apart from these similarities, learners rated teachers' understanding of their problems in learning as the next most important features whereas the teachers valued their ability to encourage students to get involved in learning activities.
Finally, evidence from the qualitative data collected from the open-ended question (question 6 in the teachers' survey) further triangulated and reconfirmed a high level of convergence between the learners' and teachers' perceptions. Among the qualities that the teacher participants suggested as most important for effective teaching, attitudes towards the teaching career was the most commonly suggested qualities as mentioned by 18 teachers. This attitude was further specified, by most teachers, as being passionate and enthusiastic in teaching and friendly in interacting with learners. Closely followed this attitude was the importance of the teachers' SMCK, listed by 14 teachers. This general category was elaborated as the ability to use English effectively for communication in life and teaching as well as a high command of vocabulary, pronunciation and grammar. Teachers' knowledge of teaching methodology and techniques was the third most commonly mentioned attribute as described by 13 teachers. Less common qualities listed by the teachers included the ability to inspire or motivate learners (8 teachers), teachers' ability to guide and support learners to make plans for their learning (6 teachers), an understanding of learners' strengths, weaknesses and problems in learning (4 teachers), a good sense of humour (2 teachers), and the ability to develop students' autonomy (2 teachers).

Discussion and Implications
The present study was designed with a three-fold purpose. First, it attempted to identify the qualities that Vietnamese EFL learners perceived as most important for effective teachers of English. It also examined the differences in the perceptions held by the three different groups of learner participants. Third, it investigated the extent of convergence of the learners' perceptions and their teachers' beliefs. In this section, main findings in relation to these three focuses and their implications for teaching effectiveness will be discussed.
With respect to learners' perceptions of the importance of the three overarching categories of teachers' knowledge base, it was found that SMCK was most highly ranked, compared to PCK and teachers' identity and interactions with learners. To a large extent, this general finding diverges from the results reported from previous studies by Brosh (1996), Barnes and Lock (2013) and Moradi and Sabeti (2014) in which PCK was found to be ranked as most important quality that effective teachers need. In particular, the three most important aspects of teachers' knowledge that the learners in this study highly valued were knowledge of vocabulary, grammar and their general competence in using English for communication. Similar findings concerning the significant value of teachers' language competence was also reported in Tran's (2015) and Ramazani's (2014). However, it should be noted that learners in the present study prioritized teachers' knowledge of vocabulary and grammar over their language competence. In this sense, the learners had a tendency to believe that to function effectively as EFL teachers, a good repertoire of English vocabulary and structures serves as the most crucial foundation. Given that in the Vietnamese context where the Communicative Language Teaching (CLT) approach has been introduced as a mandated teaching method and gained increasing popularity, teachers in this content might, to some extent, mistakenly downplay the role of grammatical knowledge in their teaching practice (Nguyen, 2018). Evidence from the learners' ranking in this study, however, indicated that teachers' grammatical knowledge is still seen as a vital component that helped form their credentials to students.
Evidence from the present study also indicated that the teachers' attitude towards the teaching career and their manner in interacting with learners were viewed as of crucial importance to the learners. In particular, it was found that learners highly expected the teachers to be enthusiastic in teaching, willing to continuously update and improve professionally, friendly to students and willing to respond to learners' questions and treat all students on a fair basis. These results echo what Pennington (1990) proposes as teachers' attitudes as well as Brown's (2015) concepts of teachers' interpersonal skills and personal attributes. These findings also display a high level of resonance with the results reported by studies conducted by Chen (2012), Chen andLin (2009), andKoç (2013), informing that teachers' personal attributes such as enthusiasm, friendliness, patience, caring, kindness and fair treatment were all highly ranked as most crucial qualities of effective teachers. The resonance of the findings seems to indicate a typical fact that Asian learners (e.g., Chinese, Korean, Vietnamese) appear to appreciate their teachers more from the emotional, motivational and interpersonal aspects where good rapports, respect and caring from the teachers might become strong motivation for learners to make efforts and achieve more in learning. This fact, in turn, might signal teachers in these contexts that although their SMCK and pedagogical knowledge and skills are important for helping them gain professional credentials from the learners, it is their attitude towards the career and the way they interact with the learners that determine how much learners engage in learning and make attempts to achieve the desired outcomes.
Another important finding from the study was that, in consistency with the results reported in Tran's (2015) study, the teachers' knowledge of society and culture of English-speaking countries together with their competence in applying IT in teaching appeared to be underrated by the learners. Socio-cultural knowledge, especially intercultural communicative competence, has been well established as one of the most crucial aspects for language teachers and learners to master (Byram & Wagner, 2018) if they are to ensure the ability to function well in the age of worldwide integration and multicultural communication context. The fact that the learner participants in the present study appeared to downplay the role of this particular knowledge component suggests a potential lack of awareness among the learner population in relation to what is important to master when they try to improve their language ability. In addition, given that technology and its widespread applications in education, as in the form of blending learning, has provided teachers with tremendous opportunities to make lessons more interesting and effective, the fact that this ability was undervalued by the learners might indicate limited applications of technology by teachers in this context. It might also signal a disbelief held by the learners about the values of its use in teaching and learning. As such, it could be significant for teachers in Vietnam and similar settings to further raise learners' awareness of the values of both a good command of socio-cultural and intercultural knowledge and the benefits in applying technology in language teaching and learning.
With regards to the differences in the perceptions held by the three student cohorts in the study, as presented earlier, no significant discrepancies were found with their general rating of the overarching categories of qualities of effective teachers. However, it should be noted that some differences among the three groups with respect to individual attributes could provide important indications for teachers and school administrators. For instance, it was found that the teenager groups more highly valued the teachers' respect and care for their problems in learning as well as the teachers' ability to maintain discipline in classroom contexts. This preference might hint that for teachers who work with teenage learners, it is of crucial importance to treat learners from a more interpersonal and motivational perspective first before aspects of language competence, knowledge or pedagogical techniques or skills are addressed. In addition, provided that IELTS learners had a tendency to put more trust on well-qualified teachers with higher proficiency level and native-like accents, it might be more appropriate for schools to schedule teachers who meet these important standards to teach IELTS classes if learners' confidence in the teachers' competence and their teaching approaches is what the schools desire.
Finally, some of the divergences in the learners' and teachers' perspectives in relation to what makes effective teachers also signal important implications that are worth discussing. To be specific, evidence suggests that while in general teachers prioritised more on pedagogical and teaching content aspects, learners placed more emphasis on the emotional and motivational angle. For instance, the teacher participants highlighted the role of their language knowledge and competence, and teaching methodology as most important. Learners, however, gave more credits to the teachers' attitudes towards the teaching career as demonstrated through the teacher' sense of responsibility, enthusiasm and an open mind for continuous learning and improving. In addition, with regard to specific aspects of PCK, teachers highly rated their classroom management skills, the ability to adapt teaching materials appropriately to the learners and the ability to get students involved in classroom activities. However, what learners appreciated more was the teachers' ability to give encouraging feedback and understand students' specific problems in learning. This mismatch in perceptions might lead to the fact that, in teaching implementation, teachers might devote more of their time and energy on professional and pedagogical dimensions to ensure that lessons are delivered effectively. Yet, what is expected of them is more on how much they attempt to make sense of students' difficulties in learning and how to effectively motivate them. Such discrepancy appears to echo findings from Brosh's (1996) study, indicating that teachers focused more on their ability to organise, explain and clarify ideas well in teaching whereas learners more highly appreciated the teachers' availability for support after class and fair treatment to all students. As such, without due care and appropriate adjustments to minimize these differences in perceptions, teachers might unconsciously undermine the learners' motivation and confidence in their teaching approach, which might further hinder their achievement of learning outcomes (Dörnyei, 2001;Horwitz, 1987).

CONCLUSION
The present study was devoted to the exploration of Vietnamese EFL learners' conceptions of what constitutes effective teachers in comparison with the beliefs held by their teachers. Findings from the study showed both divergence and resonance with results from previous studies conducted in Vietnamese and other Asian contexts. Although teachers' SMCK and PCK were found to play prominent parts in both teachers' and learners' perceptions of what makes effective EFL in this setting, it should be emphasised that from the learners' perspective, it was more of the teachers' interpersonal, emotional and motivational aspects that the learners desired. In light of this finding, it appears to be of crucial importance for teachers in Vietnam and similar EFL contexts where learners' motivation functions as the backbone in determining their attempts to engage in the learning process and to accomplish the intended learning outcomes, to place higher priority on the construction of relationships with and trust from their learners as well as showing their due care and respect to the students. Findings from the study further reaffirmed the context-based and multifaceted nature of each category in the teachers' knowledge base and the fact that there might not be a "one size fit all" set of attributes expected by different groups of learners within the same setting. Further research in the future that investigates this particular topic, as such, might need to go into more in-depth qualitative evidence with a particular focus on specific groups of learners or language programs.