The ABCs of modal verbs
Modals are a special group of helping verbs, e.g. “can” and “could.” The distinction between dynamic, epistemic, and deontic uses of modal verbs is one of the most puzzling pieces of the verb system. For me, the easiest way keep things straight is with the mnemonic ABC: for ability, belief, and canon. So when you encounter a modal, ask how it is being used. Is it A, B, or C?