Pedagogical Strategies In Knowledge-Building Of English-medium Instruction Classes ——Based On Epistemic Semantic Density

Implementing English-medium instruction（hereafter EMI）is an important means for higher education institutions in non-Anglophone countries to pursue the internationalization of higher education.EMI courses in higher education institutions focus on teaching disciplinary knowledge though English,and helping students command academic knowledge through cumulative knowledge-building.Nevertheless,most of the existing studies focus on how to promote communicative effectiveness of pedagogical strategies.How do teachers build knowledge,and what is the role of pedagogical strategies in EMI courses remain under-researched.The dimension of semantics in Maton’s（2013,2014a）Legitimation Code Theory（LCT）,which focuses on knowledge-building,has been widely employed in the field of education.Existing semantic research that explores classroom teaching mainly focuses on documenting the types of semantic profiles and the pedagogical strategies involved in the knowledge-building processes.However,previous studies have only drawn trend lines of semantic profiles based on general descriptive analysis.Focusing on the concept of epistemic semantic density（hereafter ESD）from semantics,and employing Maton and Doran’s（2017a）translation device and Barreto et al.’s（2021）value assigning methods,this thesis explores the features and roles of pedagogical strategies in knowledge-building processes in Chinese EMI classrooms.This thesis adopts the method of case study.Data are collected from two EMI courses with high proportion of English instruction in a top university in the east of China.One course is social psychology（teacher 1）,which has approximately 90% of English instruction;the other course is international trade（teacher 2）,which has approximately 99% of English instruction.This thesis conducts a 16-week classroom observation and analyzes video recordings of the two courses.Two chapters in each of the two courses are transcribed（90177 words in total）,coded and assigned values.According to the above analysis,this thesis 1)explores the overall knowledge-building of the EMI courses;2)analyzes the types,frequencies,and linguistic features of pedagogical strategies in cumulative knowledge-building processes;3)investigates the negotiation of complexity of words in cumulative knowledge-building,and the role of pedagogical strategies in the negotiation.The following conclusions have been drawn.Firstly,in the processes of knowledge-building,plain words are the most frequently used wording types.Lectures exhibit relatively fair ESD ranges.In terms of ESD profiles,Teacher 1 builds knowledge mainly through recursive ESD waves,single ESD waves and downward ESD shifts;Teacher 2 builds knowledge mainly through recursive ESD waves and single ESD waves.Secondly,5 types of pedagogical strategies are observed in cumulative knowledge-building,which can be categorized into unpacking strategies and repacking strategies.Among the pedagogical strategies,“giving concrete examples”,“using everyday L2”,and “using previous knowledge” mainly serve as unpacking strategies;“using everyday L2” can also be repacking strategies,other repacking strategies include “recapping terms” and “restating”.Unpacking strategies outnumber repacking strategies.This thesis also examines pedagogical strategies from the perspectives of the wording type and ESD entry and ESD exit.In terms of the wording type,plain words are the most frequently used wording types.In terms of ESD entry and ESD exit,unpacking strategies mainly exhibit high or low ESD entry and low ESD exit;while repacking strategies mainly exhibit low ESD entry and high or relatively high ESD exit.Thirdly,in terms of unpacking strategies,teachers employ the strategies with high ESD entry and low ESD exit to weaken ESD,and employ the strategies with low ESD entry and low ESD exit to keep the ESD weak.In terms of repacking strategies,teachers employ strategies with low ESD entry and high ESD exit to strengthen ESD.This thesis combines the dimensions of semantics and specialization to discuss the conclusions from the aspects of university,discipline,syllabus,teachers and students.This thesis proves that Maton’s LCT Semantics can be applied to explore pedagogical strategies in EMI contexts,sheds light on the exploration of pedagogical strategies in EMI contexts,and provides inspiration for improving EMI pedagogy.