Grammatical Metaphor as a Means of Expressing Modality in Vietnamese Film Dialogue

Abstract

This paper investigates modality metaphor as a resource for construing negative meaning in Vietnamese film dialogue within the Systemic Functional Grammar framework. The dataset comprises dialogic discourse from 25 Vietnamese feature films (1974-2023), collected from public sources, transcribed, and normalized. The analysis yields 74 instances of modal metaphor expressing negation. Notably, all instances realize subjective modality, with no evidence found for objective modality. The data converge on two dominant patterns: (i) Speaker + (không) + Mental Verb + Core Clause; and (ii) Ai + mà + (không) + Core Clause. These patterns enact, respectively, the personalization and generalization of stance, which mitigate negation, reduce direct confrontation, and expand the negotiability of meanings in interaction. The study contributes to Vietnamese modality research by foregrounding grammatical metaphor as an explanatory mechanism and suggests extending the analysis to other modal values and to comparisons with everyday spoken interaction.