Welcome to the Grammar Minute, where we’re saving the English language sixty seconds at a time! I’m Lauren Smith, and I am going to visit the house of my parents. That … sounds really weird, and stilted, and formal, you say. To which I answer: Why doesn’t “house of Representatives” sound equally weird?

This isn’t just custom—it’s an actual rule. In languages besides English – such as Russian, for example – there’s no difference between “mom’s cat” and “the cat of my mom.” There’s only one way to put it. English, however, differentiates between whether the possessor of the thing is human, sort of human, or not human at all. It sounds weird to say “the keyboard’s keys,” but it’s fine to say “the keys of my keyboard,” because the keyboard isn’t human. Conversely, it sounds kind of weird to say “the collar of my cat” but normal to say “my cat’s collar” because cats, at least compared to keyboards, are human-ish. The general rule is: Living things get apostrophe plus s. Nonliving things get “of.”

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