The Construction Of Causality In The Stratification Perspective Of Language

Halliday attached great importance to the study of scientific discourse,which is a new research direction in the field of Systemic Functional Linguistics in recent years.Physics is the foundation of science and physics textbooks are important media to transfer the knowledge to students.Starting with the lexicogrammatical features of discourse in physics discipline,it is helpful to reach an effective path to solve the dilemma of discipline education(Li,2018).The causality construction is an important means of decoding and encoding scientific knowledge.This study takes an American university physics textbook as the research object to investigate the construction modes of causality,helping students better understand physics language and knowledge.Based on the multi-stratal perspective of language in SFL,this study combines a qualitative approach with a quantitative one to analyze the clauses and clause complexes,which construe causality,in the mechanics textbook,An Introduction to Mechanics.This thesis investigates how the causality is realized between clauses and inside a clause in the lexicogrammatical,semantics and filed strata,and explores the linguistic resources for causality construction in theses three strata.The analysis of these three different strata can facilitate our understanding of the causality construction in the physics textbooks.This research has engendered the following major findings.Two different construction modes of causality between clauses are found in this physics textbook,including(1)the logical connection between figures and(2)the direct connection between figures.The direct connection between figures is realized by non-finite verbal group in the lexicogrammatical stratum.As to the causality inside a clause,there are three construction modes:(1)causality packed into a material Event,(2)causality packed into a relational Event and(3)causality realized by circumstantial element in figure.The frequencies of these construction modes are compared,and authors of this textbook prefer to use the first construction mode of causality between clauses,namely the logical connection between figures.In this kind of mode,conjunctions are used to connect clauses which have the cause-effect relationships.In the construction of causality inside a clause,the ideational metaphor plays an important role,which construes the remapping of figure and makes the figure become the elements of a figure.The analysis of the construction modes of causality in physics textbooks is helpful for students to understand physics knowledge more easily when they study physics.