Why Is This a Question?

Why don't eleven and twelve end in -teen? The rest of our counting system sits in neatly arithmetical sets of ten, so why do these two rulebreakers seem so at odds with the numbers that follow them? Admittedly, that's probably a question that might never have occurred to you. But if you're even remotely interested in the origins and oddities of language, it's likely also a question you're now intrigued to know the answer to. Everything about the origins and oddities of language you never thought to ask.