ABSTRACT
As another significant part of the book, this chapter concentrates on discourse structure, extending syntactic dependency to discourse dependency. Homogeneity of the sub-corpora is validated. In a similar pattern as at the syntactic level, the author examines the discourse dependency relations, discourse valencies and discourse dependency distances (DDs). Like syntactic DD, there is a threshold of discourse dependency distance (3–5), which might result from human parsers’ limited capacity of working memory. Furthermore, the author examines whether there is a top-down instalment at all the three levels (forming sentences from clauses, forming paragraphs from sentences and then forming the whole discourse from paragraphs). The body of the news reporting also goes with a macro-proposition on top and bears a top-down schematic instalment organisation. Also visually and empirically presented, rhetorical structures at the sentence level are found to differ from grammatical structures to a certain degree.
