This module teaches learners about expressing permission, obligation, and prohibition using modal verbs. It discusses the different modal verbs used for each: may and can express permission, have to, must, ought to, and should express obligation, and mustn't expresses prohibition. Various activities are provided to help learners identify and correctly use these modal verbs, including a prayer, fill-in-the-blank questions, and creating a table of family values. The goal is for learners to understand and apply modal verbs in expressing these concepts.