This document discusses modals and semi-modals in English. It defines modals as helping verbs that do not change form based on tense and are always in the base form. Semi-modals are similar but do change form based on tense or subject. The document provides lists of common modals and semi-modals and examples of their uses, including ability, requests, permission, assumptions, past ability, suggestions, possibilities, and obligations. It also discusses word order and gives additional examples to illustrate the meaning and uses of different modals.