1. 研究目的与意义（文献综述包含参考文献）

Literature Review In this chapter, the literature review and theoretical framework consists of three sections. Section 2.1 introduces the philosophical background and the development of presupposition briefly. Section 2.2 mainly reviews the characteristic analysis of presupposition and the triggers at lexical and syntactic level, also gives explanation in detail about the important roles of pragmatic presupposition in writing. Section 2.3 looks back to research discovery about pragmatic presupposition in writing and points out the gaps, which lays theoretical background for the following experiment. 2.1 The philosophical background and development of presupposition Presupposition, which refers to the inferences about what are assumed to be true in the utterance rather than directly asserted too be true, can be divided into semantic presupposition and pragmatic presupposition, and each of them have their own application. This dissertation mainly discusses the functions of pragmatic presupposition in English writing. As an experiential basis and secondary condition, pragmatic presupposition plays an important role in writing. About one hundred year ago, Gottlob Frege (1892), who was known as the German philosopher, logician, and mathematician, firstly raised presupposition as a philosophical term in his book named On Sense and Reference. In his production, he stated that any sentence proposition exists an obvious presupposition, meanwhile, the pronouns used in the sentence have references. After Frege, the British philosopher Bertrand Russell (1905) and Peter Strawson (1952) made researches from the perspective of semantic presupposition, which pushed the study of presupposition into a new stage. As a result, it no longer belonged to the field of philosophical research, but a linguistic research. When it comes to the1970s, with the development of semantics, Noam Chomsky (1971) proposed the analysis of presupposition and the focus with his ”Deep Structure, Surface Structure, and Semantic Interpretation”. 2.2 Properties and roles of presupposition The features of presupposition can be generally summarized by two aspects. On the one hand, the linguist He Ziran (1997) states appropriateness and common ground in his book Contemporary Pragmatics. On the other hand, another linguist Chen Xinren (1998) states unidirectionality, subjectivity and concealing in his book A Survey of Pragmatics. Then, what about presupposition triggers? Presupposition is triggered by definite descriptions: the simple or compound proper names and temporal clauses, and is soon extended to all kinds of other syntactic structures (Keenan, 1971; Karttunen, 1973) and lexical items (Kiparsky, 1970; Fillmore, 1971a). The roles of pragmatic presupposition in writing can be generally summarized by three items based on definitions and properties of pragmatic presupposition. Firstly, it makes the text more coherent and logical when served as a linking device between the very sentence and the forthcoming one or the previous one. Secondly, considered as information structure, it conduces to make the information more informative and continuous, so that the macrostructure of a discourse can be organized better. Thirdly, it is a necessary aspect of writing which makes effort effectively in both expressing and understanding sentence meanings. 2.3 Related studies about pragmatic presupposition in writing Presupposition has been a significant topic in linguistics, and writing is a crucial measure of students#8217; English level. Therefore, plenty of researches about pragmatic presupposition in writing teaching have been done. For instance, EFL teachers from Jilin University used product approach and process approach to prove that pragmatic presupposition play a facilitating role on teaching English writing. Besides, according to Wang Lifei, the technology of error analysis has been made good use of by teachers in an informal and intuitive way. Whereas these studies usually drew lessons from the theories of domestic and foreign linguists and scholars, including the theories of Leech, Levinson, Miao Xingwei, Zhang Keding, and Zhu Yongsheng etc. There are two aspects of the gaps in pragmatic presupposition discovery: The present studies made by linguists mostly focus on establishing theoretical models for pragmatic presupposition, rather than practical application. Besides, they usually directed its effects on writing teaching, seldom on the students themselves.

2. 研究的基本内容、问题解决措施及方案

Methodology In this composition, a study has been conducted to study the effect of pragmatic presupposition on EFL learners#8217; writing, including research questions, data preparation and the methods. According to EFL learners#8217; writing test with different tasks, people would better understand what an effective way pragmatic presupposition offered for EFL learners#8217; writing. In order to achieve this purpose, the following procedures had been adopted. 3.1 Research questions Taking the research gaps mentioned in the literature review into account, this study would answer the following questions: 1. Is there any significant effect in improving students#8217; writing scores if they learned pragmatic presupposition? 2. When doing self-assessment, does pragmatic presupposition benefit the students#8217; writing skills? 3.2 Subjects The current study#8217;s subjects involve two classes consisting of 70 students of third-year English majors. They are all Chinese speakers, around 20 years old and have learned English mainly in the classroom following teachers#8217; instructions. All participants are university students. 3.3 Instruments and methods There are three data collection instruments in this study: firstly, in order to measure the subjects#8217; English writing proficiency before they learned pragmatic presupposition, the scores of TEM-6 writing in sophomore year were used. (The total score of TEM-6 writing is 107.) The reason for choosing the material from TEM-6 lies in the validity, reliability and practicality of TEM-6. Secondly, the research needs the score of subjects#8217; writing course in the second semester junior#8217;s final exam. These two parts#8217; data were taken from two classes#8217; students majored in English. Due to the particularity of English majors, it is known that students learned pragmatic presupposition theory in linguistic course in junior year. Therefore, the first question mentioned in the 3.1 part can be solved by comparing these two sets of data. To do the calculations, the research used the SPSS procedure, and to analyze the collected data, independent samples t-text was involved. Thirdly, as for the second question raised in the 3.1 part, the study used a self-assessment questionnaire to complete. The subjects need to answer the question about whether they have improved writing skills by learning pragmatic presupposition on the questionnaire, such as content relevance, coherence, organization, language quality, etc.