1.2 Significance of the Research
Study on metadiscourse has provided the researchers with a new and efficient way for the discourse analysis especially research in news discourse. Huang Min explored the metapragmatical function of the quotation in the news report and reveals how the reporter puts his/her own voice while quoting the others in a seemingly balanced approach (Huang Min, 2008). Huang Qin and Xiong Yao made a comparative analysis of the use of metadiscourse and explore the reasons behind the similarities and differences in both English and Chinese News Commentaries (Huang Qin and Xiong Yao, 2012). Zhou Fen (2011) also proved with details that the wide use of metadiscourse contributes a lot to the realizing of news’ genre features based on VOA news samples. Most of the researches are conducted from a perspective of news media or linguistics, or both of them.
What’s more, a popular trend can be seen in the news research. That is most researches were set on some special social groups such “90s” and “White collar in metropolis”, such groups have emerged since China’s Reform and Open policy in 1980s and become shining in today’s social lives. Among all such groups, migrant Workers are generally believed to be one of the most important and complicated social factors. Huang Wei has revealed the language form and expression modal through studying the figure of migrant workers in news discourse (Huang Wei, 2008). The usage of metadiscourse in Chinese news report on Migrant Workers issues can lead listeners to a better understanding of the information as well as the speakers’ attitude towards the news events. And from this perspective, this paper is also of great significance for news practitioners to build up a harmonious steering of public opinion and healthy conviction involving in Migrant Workers issues.

1.3 Structure of the Thesis
In this paper, first we give a brief introduction. Then in part 2, we make a clear definition and classification of metadiscourse and introduce previous studies on metadiscourse. Part 3 gives all the research questions and specific research method. In part 4, we demonstrate our research finding and our analysis supported with statistic data. The last is the conclusion of this paper.

2 Previous Studies on Metadiscourse
2.1 Definition
Since the notion of “metadiscourse” was put forward by Harris in 1959, the researches of this field have undergone for more than half a century. It was not until the 1980s, however, that the research of metadiscourse made breakthroughs and won worldwide concern in textual linguistic area. Therefore, most researchers have given their own versions on the definition of metadiscourse. And hereby we shall discuss the most representative and classic ones among them with time order.

The first figure we stress much emphasis on is Vande Kopple (1985). He believes that metadiscourse is "discourse about discourse" and shows the author's or speaker’s intention, more exactly metadiscourse is a mean to interact with his receivers in his contend, especially with his readers in written text. His definition comes from his early thought which a text generally contains different levels of meaning. They are at least two: propositional and metadiscoursal meaning. The former offers information the author or speaker wants to convey in his text. Here, the information is label as propositional content. ( Propositional content: propositional material, something that can be argued about, affirmed, denied, doubted, insisted upon, qualified, tempered, regretted and so on (Halliday, 1994:40), it is likely regarded as propositions that can be identified false or true.) The latter, that is the level of metadiscourse, with no propositional material, can help the receivers organize, classify, interpret, evaluate and react to such material. Hence, metadiscourse is defined as discourse about discourse, or we can say, communication about communication. 汉语新闻语篇中民工形象的元话语分析(2):http://www.youerw.com/yingyu/lunwen_13226.html