Why do we add S to some words but ES to others? And when a word ends with Y, how do we know whether to change the Y to I before adding the plural suffix? And why on earth does knife become knives? You can unravel these mysteries with six simple rules.
The History of the English Language in a short, funny movie. Great on the first day of school when I ask them, "Why do you think four years of English class is necessary? What is the purpose of teaching English?"