Mood and Modality in English

This chapter is focused on the main markers of modality in English, that is, modal verbs. We first give a definition of modality and mood and briefly discuss the different forms used to express modality. We then outline the formal properties of modal auxiliaries and the way in which these properties may lead to a classification of some verbs as more central to the category of modal auxiliary than others. The main part of the chapter is focused on the meanings of modal verbs, and the different taxonomies that have been proposed in the empirical literature of ways to categorize modal meanings of possibility and necessity. In the course of the discussion, we pinpoint some key questions that have been and still are sources of debate in the field.