(D）The multi-dimension functional approach to MSAs could lead to a fruitful understanding about the nature of language based on a combination of various factors such as cognition, pragmatics, evaluation and text types.In this sense, the theoretical framework that was advocated in this dissertation should be regarded as an extension to the parts concerning modality in SFL.
(E）In this dissertation the qualitative and quantitative methods are combined in the study of MSAs as a means of modality supplementing.Such a practice reminds people that language study should not stay at the level of theory only; instead, it must be based on practice.
(F）This study does not deviate from the practical situation of English teaching in China.It strongly proposes that the EFL teaching methodology and textbooks be tailored somehow to keep the students better informed of the interpersonal functions of MSAs.
(G）This dissertation is based on authentic corpora.The authentic corpora include downloads from e-journals, and extracts from printed journals and monographs, as well as experiment subjects’ performance.Since the corpora are large in size, their validity is guaranteed as well.This is a positive response to the appeal made by SFL and corpus linguists that the analysis of authentic corpora can be significant both theoretically and practically.
The biggest achievement that this dissertation has made is the exploration of MSAs as a means of modality supplementing.Such a study has never been explored in detail before.In this sense the current study is original.Since the theory that MSAs are a means of modality supplementing for various reasons has been testified through the corpora analysis of four genres and the teaching experiment, it holds water to a large extent.It is hoped that the research results of this dissertation will be helpful to language researchers, discourse or text analysts, dissertation writers, and the students and teachers of English in China.
7.4 Limitations and suggestions for further research
This dissertation has achieved some positive results in studying modality.Nevertheless, modality is a complex and extensive field of language use; it is natural for people to find that there are some parts of the research that need to be improved.There are two main limitations in this study:
(A）The corpora are still limited in size and type.One of the main issues that linguists are concerned with is the selection of corpora.The current study has paid much attention to the typicality as well as the size and validity of corpora.Yet, even such cautious acts can be faulty here and there.To start with, the corpora should be expanded in size.Large corpora speak louder than smaller corpora.Also, modality is not just rich in the four genres that have been studied.Other genres such as classroom interactions and movie scripts might be the fascinating areas for the research on modality, particularly modality supplementing.
(B）Other means of modality supplementing have not been studied in detail, due to the constraints of space, energy and resources.Modality supplementing does not involve MSAs only.Other patterns of modality supplementing such as modal adjective + MV and MA + lexical verb can be investigated and they may further reveal the roles of pattern grammar in discourse.Such an orientation of research caters to the appeal many corpus linguists have made, i.e.pattern grammar is more convincing than or at least a complementary reference grammar to pedagogical grammar (cf.Tognini-Bonelli, 2001).
It is suggested that future studies concerning modality supplementing be made in the following four aspects.
First, the corpora should be larger and more diversified.If the corpus for each genre could reach the size of over 1 million words, the statistics would be more convincing.Also, if more genres could be selected for comparison, the result would be more instructive.
Second, comparative research can be made on MSAs and other modal devices as means of modality supplementing between English and Chinese.For instance, a comparative study on the use of supra-segmental or prosodic units such as rhythm, pause and pitch between Chinese and English might be interesting.Chinese has different linguistic devices for modality supplementing such as modal particles (e.g.ba, ma, a, and la); in contrast, English lacks such expressions in written forms though in spoken form intonation can indicate modality to some extent (cf.Hewings, 1998: 317-333).A contrastive study on MSAs and other devices as means of modality supplementing between Chinese and English is worth doing later.
Third, more attention should be paid to modality supplementing in relation to EFL.If much attention is paid to this area, more understandings will be gained about the strategies of language learning.In turn, this will be beneficial to the modification of syllabus design and the improvement of teaching methodology.
Fourth, CDA and positive discourse analysis (PDA）(cf.Martin, 2006; Zhu, 2006）can be done through MSAs as a means of modality supplementing.This study has revealed something about how ideology works in different types of discourse.It is believed that this can be a potentially fruitful area of CDA and PDA.