Q: What’s the correct way to make a possessive of a word that’s already possessive? Do you say McDonald’s's fries? Or St. John’s's team? It seems wrong to use one ‘s right after another ‘s, but I can’t think of a better way to do it.
A: When a name already includes ‘s (like McDonald’s or St. John’s), the name is treated like a normal noun rather than a possessive. So you’d say “The local McDonald’s is always busy” or “We’ll be playing St. John’s next Tuesday.”
Technically, you’d make a name like that possessive by adding ‘s. But this would result in a monstrosity: “The local McDonald’s's parking lot is always full” or “We’ll be playing St. John’s's team on Tuesday.”
In practice, usage guides recommend avoiding such a construction, for obvious reasons! It’s usually easy to rephrase the sentence: “The parking lot at the local McDonald’s is always full” or “On Tuesday we’ll be playing the St. John’s team.”
A little possessiveness can go a long way.
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