Can

As a modal verb, 'can' expresses ability or possibility, as in 'I can swim.' As a noun, a can is a metal container for food or drink, and as a verb, it means to put food in cans or to dismiss someone from a job (informal).

The verb comes from Old English 'cunnan' meaning 'to know how, to be able.' It gradually turned into a modal helping verb and lost many normal verb forms. The noun 'can' is from a different root, from Old English 'canne' meaning 'container' or 'cup.'