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Q. I belong to an editing group. In these two sentences, we believe the commas belong. Is there a name/description for this or a rule you can direct us to? “It’s what makes a barn, a barn.” “Whatever will be, will be.” That comma.
A. The closest rule seems to be the one at CMOS 6.55, described as “commas between homonyms” and offering examples like “Whatever is, is good.”