An Analysis Of Themes And Thematic Progression Patterns In English Science Speeches

Since Mathesius defined the Theme and Rheme of a clause, many other linguists also made great contributions to Theme-Rheme theory. Thematic progression which refers to the connection with Themes and Rhemes of different clauses in a text also draws much attention at home and abroad. These two theories provide a new aspect for discourse analysis. Halliday, a systematic-functional linguist, makes a classification of Themes based on different standards, and elaborates on the Themes of special sentence patterns. F·Danes, a Czech linguist, studies the Themes and Rhemes with a focus on the connections of Themes and Rhemes in different clauses in a text. He(1974) puts forward five thematic progression patterns after analyzing substantial proportion of texts. Some famous linguists in China, such as Xu Shenghuan(1982), Huang Yan(1987) and Huang Guowen(1988), also propose some different thematic progression patterns based on a large number of researches. Since then, Themes and thematic progression patterns are applied to analyze texts of different genres, such as news, advertisements, and speeches. However, the related studies of speeches from the perspective of Themes and thematic progression patterns are confined to political speeches and student‘s speaking contests, while science speeches draw little attention from the researchers.Science speech is a kind of general public speech, and it shares the common features that general public speech has. Furthermore, it has its own peculiarities. The research materials of the thesis are about science speeches from TED, which not only aim at introducing scientific findings that the speakers find in natural sciences, humanities or others, but also involve the research methods on which the findings are based. The thesis selects 10 science speeches from TED official websites and makes a detailed analysis of them based on Halliday‘s Theme-Rheme theory and Huang Yan‘s thematic progression patterns. And this thesis is mainly a qualitative research assisted by a quantitative method. Here are some findings:(1) In English science speeches, multiple Themes are the most preferred ones with the highest proportion; simple Themes come second also with a much higher percentage; clausal Themes take the least part.Among the most frequently used multiple Themes, textual Themes are much more frequently used than interpersonal Themes; among the different components as textual Themes, conjunctions hold the majority, conjunctive adjuncts occupy also a relatively higher percentage and continuatives account for the least proportion.Among the different components as simple Themes, pronouns especially the first person and the third person, have a much higher percentage than other components and nominal groups follows with the second highest proportion.In clausal Themes, complex clausal Themes are much more than simple clausal Themes.(2) In English science speeches, unmarked Themes have the higher percentage than marked Themes. In other words, the speakers tend to use more unmarked themes and marked ones. Among unmarked Themes, pronouns take the highest proportion and nominal groups come second with a higher percentage. Among marked Themes, adjuncts are more frequently used than complements.(3) In English science speeches, thematic progression patterns are complex, because there are eight models which can be identified in each of the speeches. The more frequently used ones are respectively linear patterns, concentrated patterns and parallel patterns.These findings above show that English science speeches have their own features in Theme choices and in the application of thematic progression patterns when dealing with the organization of the texts to deliver the information in science speeches. The present study puts forward the definitions of simple clausal Theme and complex clausal Theme, which enriches the Theme-Rheme theory. Moreover, the research proves that the research materials where an analysis is made on themes and TP patterns can be enlarged. In addition, the hearers may have a better understanding of contents of English science speeches with the knowledge of the findings in the study. English learners may make progress in organizing different clauses in a text in a coherent way, which can help them transit the messages naturally.