I rewrote this introduction three times. I was trying to find a good example of Zen Comma Rule AC: Put commas around the year when the month and day are included. Browsing the web for news stories with lots of dates, I kept coming up with Amy Winehouse and Casey Anthony.
I tried to use those news stories, but doing so seemed to be in poor taste. So, here you are: completely made-up examples of this comma rule. Use these examples to learn when to use a comma with various forms of dates.
1. Don’t use commas in dates when you include only the month and day.
Correct Example: The ticket counter will open on January 1 and remain open until February 14.
Notice that this example has no commas. However (and there’s always a however), you might need a comma after the day if needed by another rule, such as to introduce a non-restrictive clause that begins with which (Zen Comma Rule T), as in this example.
Correct Example: The ticket counter will open on January 1 and remain open until February 14, which is Valentine’s Day.
2. Don’t use commas in dates when you include only the month and year.
Correct Example: The August 2009 flood of letters indicated general unrest among voters.
Notice that this example has no comma between the month and year, which is a fairly common mistake.
3. Use commas in dates both before and after the year when the month and day are included.
Correct Example: We’re planning a party on June 31, 2011, to celebrate my birthday.
Notice the commas around the year. The most common mistake is leaving out the comma after the date. Both commas are required.
As with most comma rules, knowing when to use commas with dates is fairly simple–as long as you have a few clear directions and a few good examples to follow. I hope this helps.
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