Dashes, colons and commas should often be replaced by a period

Posted by June on February 3, 2025
LABELS: COLON VS PERIOD, COMMA VS PERIOD, COPY EDITING, DASH VS HYPHEN, DASH VS PERIOD, GRAMMAR, PUNCTUATION

Are you a dashaholic? It’s a thing, apparently. I’m more of a colon abuser myself: as if everything I write is so important it requires the colon’s drumroll effect. I’ve known more than a few comma junkies, too.

No matter your punctuation poison, there’s an easy antidote. The period. Let’s look at the role of each of these marks and how not to abuse them.

Dashes are widely misunderstood. A lot of people call hyphens dashes. Heck, even I call hyphens dashes when I’m reading my insurance policy number over the phone: “Two, nine, three, dash, one, one, eight.” But in text, dashes are something quite different. Unlike hyphens that connect a word with another word, prefix or suffix, as in “best-dressed,” dashes work at the sentence level — like this.

Dashes have two main jobs. A dash can signify an abrupt change in sentence structure — a shift like this that doesn’t fit with the grammar of the first part of the sentence. Or a dash can work like parentheses — setting off lists, parenthetical information, etc. — when you feel parentheses won’t cut it. Rules for dashes do not say you can use them to join complete clauses — this clause is an example. This is one of the most common abuses of the dash I see — people use them to string together two things that could stand alone as sentences. I suppose a loose interpretation of that “abrupt change in sentence structure” rule makes this OK. But when I’m editing, I make each clause into its own sentence, separating them with a period.

By the way, we’re talking about em dashes, not en dashes, which are shorter, less widely used and have more in common with a hyphen than with a dash. En dashes are often seen in compounds like “post-World War II,” connecting longer names and proper names with prefixes and other words. Dating back to days when newswires couldn’t transmit certain marks, news media have traditionally avoided the en dash and today just use a hyphen instead.

Colons are similar to dashes, just with a little more oomph: They set off an idea from a main sentence, but they suggest a greater emphasis. This can be a single word, as in this Associated Press Stylebook example: “He had only one hobby: eating.” Or one or more complete sentences can follow the colon. If the words that follow the colon don’t make up a complete sentence, don’t capitalize the first letter. But if one or more sentences is introduced by a colon, capitalize the first letter. Never double-space after a colon.

Colons can also introduce examples and lists, as in this sentence from the Chicago Manual of Style. “The watch came with a choice of three bands: stainless steel, plastic or leather.” But never use a colon after the word “including” to set up a list. “The watch came with a choice of four bands including stainless steel, plastic and leather.””

Colons that scream “listen to what I’m about to say” too loudly should probably be replaced by a period. I’ll try to take my own advice on this.

Commas have a lot of jobs, but they can’t connect two independent clauses without an “and,” “or” or “but.” This sentence is an example of a comma splice, you shouldn’t use commas this way.

Technically, a semicolon can link independent clauses. But they shouldn’t because — well, yuck. Semicolons to link clauses make sentences longer and less readable with nothing to gain except a chance for the writer to show off her knowledge of semicolons. Rude.

Dashes, colons and commas have a proper role to play between clauses. But if you’re using them to cram multiple ideas into a single sentence, ask yourself whether a period would make the passage more palatable to your reader.