What does this sentence mean?
Happy birthday to Besse Cooper, the world’s oldest person who turned 116 today.
a. It’s a birthday greeting for Besse Cooper. She is the oldest person in the world and she turned 116 today.
b. It’s a birthday greeting for Besse Cooper. She is the oldest person in the world and she is the eldest of some unspecified number of people who all turned 116 today.
Besse Cooper actually turned 116 yesterday and the greeting went out on Twitter. You need to add a comma after “person” to indicate that “who turned 116 today” modifies Besse Cooper. The comma is what indicates a parenthetical phrase, so that the sentence means “Besse Cooper turned 116 today. She is the world’s oldest person.”
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