Chapter 4　GIobaI Coherence in the EngIish Learning Advertisements

As suggested in the review of literature on global coherence in Section 2.1.3，the discussion of global coherence is almost exclusively done in purely verbal texts.Although the essential role of the global coherence in the construction of discourse coherence is widely acknowledged，global coherence has induced a heated debate in discourse analysts and text linguists from various perspectives.It has been discussed with different yet interrelated terms such as discourse topic，macro-structure and organization.It is also believed to be closely related to the external factors like context and reader's mental schema.Global coherence is getting even more complicated in the case of multimodal discourses where multiple semiotic modes are involved.There have been relatively few research efforts in this direction.Therefore it is still largely unknown how resources from different semiotic modes are integrated to form a complex discourse with hierarchical global structure.In this chapter，the goal is to explore how global coherence is constructed through the combination of resources from different semiotic modes—verbal and visual—in the English learning advertisements as a special genre of multimodal discourses.

For this end，a clear definition and operational model of global coherence are needed in order to provide guidance for the analysis of the semiotic configurations in the data.Therefore，in Section 4.1 a working definition and model of global coherence in the multimodal English learning advertisements will be proposed.It assumes that global coherence is constructed through the force of a discourse topical structure which consists of topics and points of various levels.Section 4.2 and 4.3 will analyze how global coherence is constructed in these advertisements through an in-depth analysis of the data.Specifically，Section 4.2 will introduce the way to identify topics and points of various levels in these advertisements.The analysis in Section 4.3 will be performed in a stagespecific manner.That is，the global topical structure of the visual part and verbal part in each of the component stages in the English learning advertisements genre will be analyzed specifically.