By Julia Wallace | January 10, 2023

My first “real” job after college was as a copy editor at a local newspaper. I spent eight hours a day turning hyphens into em dashes, abbreviating dates, eliminating double spaces, and uncapitalizing basically everything.

Style mistakes in writing are the kind of thing that stick out glaringly and immediately to copy editors and don’t even register as incorrect to most normal people. I physically cringe when I see decades written out with an apostrophe before the S. (Like “the 1970’s.” So wrong. I explain below.) Run-on sentences make me squirm. And don’t even think about capitalizing a title if it falls after someone’s name. Yes, I am a virgo and an older sibling — why do you ask?

Listen, I’m not proposing you start sending back edits on a casual email or spell-checking your friends’ text messages. But if you’re writing or checking copy for a business’ marketing materials, you better get this stuff right!

And once you know the rules, you can’t unsee them! Just as a warning — you’re now going to notice these mistakes everywhere you look. For that, I’m sorry. Or, you’re welcome.

A caveat

These rules are pretty AP Style-based. Each brand will have different house styles and preferences. These tips are just a good foundation across the board.

Hyphens and em dashes and ellipses, oh my!

• Hyphens (-) only go between words, with no space in between — ever. Mother-in-law, life-size, and in-depth, are a few examples.

• Em dashes (—) always have a space on either side. They designate a natural break between related clauses. For example: Let’s go get ice cream — I’m hungry!

To make an em dash on your keyboard (for Mac users), hold Option + Shift + Hyphen. For Microsoft users, hold Ctrl + Alt + Minus. Or type the preceding word, two hyphens, and then the next word with no spaces in between. Like--this. That automatically creates an em dash, but you’ll have to go back and manually insert the spaces on either side of it. Here are some other ways to make an em dash.

• En dashes (–) mean “through,” typically when referring to a range of time or numbers. There should never be a space around en dashes. For example: Monday–Saturday. 11 a.m.–7 p.m. Chapters 1–4. ⅔–¾ cup.

To make an en dash on your keyboard (for Mac users), hold Option + Hyphen. For Microsoft users, hold Ctrl + Minus. Or type the preceding word, a space, one hyphen, and then the next word. Like -this. That automatically creates an en dash, but you’ll have to go back and delete the preceding space.

• Ellipses (...) are used to signify an omission in a quote or, if you’re writing casually, a dramatic pause. Treat ellipses as if they are a word, with a space on either side. If they come at the end of a sentence, you add a period, so there’s four dots in a row. Otherwise, ellipses are always three dots.

Capitalization

Only capitalize proper nouns. For example, the following words are generally lowercase:

master’s degree, artificial intelligence, birthday, organizational skills, summer, north.

Titles are capitalized when they come before someone’s name, but lowercase when they come after. E.g., President Joe Biden vs. Joe Biden, who is president. The word “president” is not in and of itself a proper noun. Neither are the words creative director, secretary, chief executive officer, or head engineer.

Ages and years

Wondering whether or not you hyphenate “4-year-old”? If the age is modifying a noun or standing in the place of a noun, then it’s hyphenated. Here are some examples of when and when not to hyphenate ages.

• Julia is 30 years old

• 30-year-olds aren’t allowed to go down the slide.

• That 400-year-old castle is so cool.

• That castle has been around for 400 years.

Remember — no apostrophes before the S in a group of years! You only need an apostrophe when you are shortening a year or decade. Here’s what I mean:

• If you’re in your 30s, you are a millennial.

• Back in the 1970s, everyone had a floral couch.

• Back in the ‘70s, everyone wore bell bottoms.

Which common copywriting mistakes would you add to this list? Email me and let me know!