Grammar girl here. Last week, Dale Siler on Twitter sent me a screenshot of a

garment ad that had a strange and unnecessary comma in the middle of the tag

line. It reads, quote, today's record, comma, is tomorrow's motivation. And that

comma violates one of the hard and fast comma rules. Never put a comma between a

subject and its verb. Commas have a lot of different uses and that's part of

what makes them confusing. Another thing that makes them confusing is that some

things are hard and fast rules, like don't put a comma between a subject and

its verb. And other things are more like guidelines as Jack Sparrow says of the

pirate code in Pirates of the Caribbean. The quote, rules about serial commas are an

example of such guidelines. The serial comma is the comma before the last

and in a series, red comma white comma and blue. That last comma before the

and is called a serial comma, Oxford comma or Harvard comma. Some people say to

always use it and other people say to only use it when leaving it out would

cause confusion. It's a style choice. But the garment ad violates a hard and fast

rule, not a guideline. My guess is that one of two things is going on. Either

the people working on the ad believe you should put a comma anywhere you would

pause when you're speaking or the tagline was originally something like

today's record tomorrow's motivation without the is which would be correct. And

then they put in the verb later and everyone forgot to take out the comma. I

make most of my mistakes when I've been rewriting a sentence to death and

overlook some preposition or punctuation mark left behind from a previous

version. So it wouldn't surprise me if that's what happened with the ad. The

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