The Function of Modal Verbs in Technical Instructive Texts Written by Women in Late Modern English

Abstract

This paper examines the interpersonal functions of modal periphrases in technical instructive texts written by women during the eighteenth and nineteenth centuries, drawing on data from the Corpus of Women’s Instructive Texts in English (CoWITE). Using a systemic functional linguistics approach, the study explores both modal forms and their discourse values, with a focus on the diachronic development of modalisation and modulation systems. Quantitative findings reveal stable modal usage across both centuries, but with a notable redistribution of core modal verbs. The qualitative analysis identifies a shift from prescriptive, high-deontic structures typical of the eighteenth century (must, will) to more consultative, evaluative, and negotiable strategies in the nineteenth century (should, may, can, might). This evolution points to a transformation in how authority is conveyed and how readers are constructed as active participants in the text. The study demonstrates that modality functions as a central rhetorical tool in shaping female authorial ethos and managing interpersonal relationships in instructional discourse. Future research should explore other instructive genres, comparative analysis with male-authored texts, and multimodal perspectives