Studies Of Transitivity Of EST Texts

Since Halliday first proposes the transitivity at semantic level, its theory and application have attracted more and more attention of linguists from both China and abroad. SFG theoretically defines that the transitivity is an important semantic system to realize experience function; it represents what happens in the real world via the lexicogrammar. EST as an important subbranch of ESP is a variety of modern English. It describes all phenomena and events in the field of science and technology. From the perspective of language function, adopting descriptive-explanatory research method, this thesis explores the transitivity in the EST texts, namely, the types of process, participants and circumstances, explaining how the experiential function is realized via transitivity in the EST texts, aiming at exploring language features of EST texts affected by experiential function.With the framework of Halliday's transitivity theory, through the analysis of a great number of examples, the present thesis systemically explicates the status of each component of transitivity in EST texts, their presence model and their influence on the EST texts production. The thesis reveals that the objectivity of science and technology determines the dominance of the material processes, relational processes and verbal processes in the EST texts and large number of metaphorical entities and a few humans participants; four major types of circumstances: location, condition, manner and purpose complement the processes to reflect the objectivity of science and technology. On the basis of the above analysis, the thesis applies the theory of transitivity metaphor to investigate the transference of the components of transitivity, namely, the transitivity metaphorization as well as its stylistic effects on the EST texts. The employment of nominalization, verbalization and passive voice gives prominence to the language conciseness and structure cohesion.The analysis of EST texts with the theory of transitivity has theoretical significance. It incardinates the conception of function of SFG and highlights the representative function of EST texts; meanwhile, it could validate the feasibility of transitivity theory and the universality of its application. With the huge increase of information in the field of science and technology, the analysis of transitivity of EST texts has also its practical significance. It provides a new perspective for the EST writers to produce the texts and also for readers to unpack the information EST texts convey, hence it may establish a new platform for the popularization of EST. EST texts as the verbal realization of writers' ideology, the choice of different transitivity processes, participants and transitivity metaphorization of the EST texts could objectively and truly reflect the event of science and technology. The transitivity metaphorization may generate stylistic effects which contribute to effectiveness of scientific and technological communication.The whole thesis is divided into five chapters. Chapter One is a general introduction to the thesis, including previous research of transitivity and the survey of EST and the concept of EST texts, the purpose and significance of the thesis. Chapter Two provides a theoretical framework the thesis is based on. It introduces the SFG's description of language metafunctions and explains the transitivity theory in detail. Chapter Three gives a practical analysis of transitivity in EST texts to establish the transitivity structure model of EST texts; on the basis of this model, three components of transitivity are analyzed. Based on the analysis of Chapter Three, Chapter Four explores the transitivity metaphorization and its stylistic effects in EST texts and Chapter Five comes to the findings of the thesis and its limitations, putting forward the suggestions for future study in SFG as well.