| Teacher’s explanation is one of the main teaching behaviors commonly used by teachers to achieve teaching objectives.Effective teacher’s explanation can show,illustrate,explain or interpret language knowledge,train language skills,impart learning methods and develop thinking ability.However,domestic and foreign research on teacher’s explanation mostly focuses on science subjects,while pays little attention to teacher’s explanation in English writing classes.Based on effective teaching,meaningful learning and ZPD theory,this research adopts Kerry’s(2002)classification of explanation types and explanation skills and Cabello’s(2018)rubric for evaluating the effectiveness of teacher’s explanation,attempting to explore the usage and effects of explanation types and explanation skills in 30 middle school English writing classes through classroom observation and conversation analysis.It aims to answer the following questions:(1)What is the distribution of explanation types and explanation skills?(2)What is the distribution of explanation skills under different explanation types?(3)What is the correlation between teachers’ usage of explanation skills and the effectiveness of explanations?Major findings are presented below:Firstly,teachers use far less reason-giving explanations than interpretative and descriptive explanations;and most explanation skills can be used frequently,but teachers lack awareness of exploiting few explanation skills like a dynamic introduction,using humor and linking the explanation with other knowledge.Secondly,teacher’s usage of explanation skills under different explanation types varies.Building in the feedback loop,introducing and using technical languages,defining key terms or concepts,and exploiting linguistic ploys are applied more frequently in interpretative explanations;developing rules and principles,building in feedback loops,exploiting linguistic ploys,using examples,using connectives efficiently,numbering points,and building in tasks are applied more frequently in descriptive explanations;building in the feedback loop,using connectives efficiently,using audio-visual stimuli,developing rules and principles,raising the cognitive stakes of explanations are applied more in reason-giving explanations.Among them,building in the feedback loop is frequently used in all explanation types.Thirdly,the higher the frequency of explanation skills is,the better the effectiveness of teacher’s explanation will be.And the frequency of explanation skills has positive correlations with all four aspects of explanation effectiveness.Among them,the frequency has a larger impact on clarity,coherence and cohesion,but smaller influence on completeness and correctness.In addition,using specific explanation skills can respectively enhance four aspects of the explanation effectiveness: Using connectives efficiently and exploiting linguistic ploys can improve the coherence and cohesion of teacher’s explanation;numbering points,using connectives efficiently,exploiting linguistic ploys,sustaining fluency and defeating mannerisms,adopting an appropriate pace can better clarify teacher’s explanation;raising the cognitive stakes of explanations,numbering points,introducing technical language,defining key terms and concepts,developing rules and principles can make teacher’s explanation more complete;avoiding the commonest errors in explaining,developing rules and principles can ensure the correctness of teacher’s explanation.Based on the findings above,this research puts forward following suggestions:Firstly,teachers should correctly choose the explanation type in accordance with the teaching materials,with more emphasis on reason-giving explanations,to help students understand the rationality of text structure and reasons for using writing skills;Teachers also should understand the functions of all explanation skills and raise the awareness to use them reasonably,thus to optimize pre-writing guidance.Secondly,teachers should choose appropriate explanation skills according to different explanation types to highlight difficult and important points.Finally,teachers should integrate specific explanation skills to ensure the clarity,coherence and cohesion,completeness and correctness of their explanations. |
