Modal verbs are explained in this slide. You can download the presentation from the link below.
Modal verbs are verbs used to indicate modality, which can be likelihood, ability, permission, request, capacity, suggestions, order, obligation, or advice. They are commonly used in English and other Germanic languages and are distinguished based on certain grammatical properties. Modal auxiliary verbs provide information about the function of the main verb that it governs. Modals have a wide variety of communicative functions, ranging from possibility (“may”) to necessity (“must”). Modal auxiliary senses include epistemic, deontic, and dynamic senses.
Examples of modal verbs include can, could, might, might, must, have to, shall, should, ought to, had better, have to, and sometimes need or dare. Modal verbs are sometimes referred to as modal auxiliary verbs because they help other verbs provide additional and specific meaning to the main verb of the sentence. Modal verbs are not conjugated, so they don’t need other auxiliary verbs.
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