A Corpus-based Comparative Study Of Thematic Structures Of English News And Editorials

Thematic structure is an essential part for textual development.The concept of theme was first proposed by the famous scholar Mathesius.Halliday borrowed this term,and later developed it into an important theory in his systemic functional grammar.On the basis of Halliday's theme-rheme theory,this thesis presents a corpus-based comparative study of characteristics of different thematic structures in English newspaper news and editorials.This is a corpus-based research.With the help of corpus linguistics,it is possible to deal with large amounts of data in an objective and scientific way.In addition,it can describe language from the perspective of the authentic usage,as the data used in this corpus-based study is collected from authentic language materials.The basic method of the corpus-based approach is probabilistic analysis,i.e.through investigating all the texts in the corpora,the probabilistic information of the language usage will be deduced on the basis of statistical analyses.The texts in the corpora are processed before any data are extracted.Firstly,the POS-tagged English newspaper news and editorial texts are so processed that each clause of the texts occupies one line and then all the concrete words are deleted,leaving only the part-of-speech tags in each clause.Secondly,different types of thematic structures are counted and classified semi-automatically,and the results are analyzed qualitatively.In addition,sample news and editorials are also taken from the corpora and used for the analysis of characteristics of different themes either in the clauses stating facts or in the clauses expressing opinions.The result is that in both the corpora used in this study the authors of the texts prefer to use declarative clauses to describe current events to the readers,and in this kind of clauses,simple thematic structures are usually the most straightforward to identify.And there are few clauses expressing views in the news corpus(ENNC),while in the editorial corpus(ENEC),there are many clauses expressing views either in a direct or an indirect way,and the thematic structures of those clauses belong to clause thematic structures.The goal of this comparative corpus-based study is to provide a relatively complete classification of the thematic structures in English news and editorials,and a description of the common thematic structures,focusing on the identification and analysis of the basic thematic structures.The present study is of significance in the following aspects:firstly,it provides an analytical and theoretical framework for thematic structure study;secondly,it can help learners to find the linguistic features of English newspaper news and editorials;thirdly,it can help readers to grasp the main information of English news and editorials,as well as help them to understand the characteristics and functions of different thematic structures.