Punctuation: Dashes and Hyphens

The next three marks we will discuss in our punctuation explanation are the em dash (—), the en dash (–), and the hyphen (-). Because all three of these marks look so similar, they are often confused by writers. They are each simple lines but have different lengths and different functions. For our discussion, we will begin with the longest and end with the shortest.

Em Dash

The em dash is named so because it is the width of the letter m. We use the em dash almost exactly the same way we use commas, colons, semicolons, or parentheses—informally, of course. The em dash is wildly popular; however, you should avoid using it in formal writing. The em dash often adds more emphasis or shows contrast. Here are some examples of how the em dash can be used.

• That girl—that beautiful girl—captured Scott's heart. (The em dash adds emphasis.)
• Pleasantville had seemed like such a wonderful place—until now. (The em dash shows contrast.)
• I would love to help—oh wait. I can't right now. (The em dash shows contrast.)
• My friends—Joseph, Rita, and Janet—will help me move into my new apartment. (Commas or parentheses could also work here.)
• There was only one thing on her mind—the treasure. (A colon could also work here.)
• I earn the money—my wife spends it all. (A semicolon could also work here.)

En Dash

The en dash is named so because it is the width of the letter n. It has two very specific and not-so-common purposes: to replace the word to in numerical ranges and to connect open compound adjectives.
Here are some examples of the en dash with numerical ranges.

• Our homework is to read pages 8–13 in our textbook.
• Shannon was living in Japan from 2009–2011.

Normally, a hyphen is used to connect compound adjective.

• A traffic jam is blocking the Utah-Idaho border.

The compound adjective ,"Utah-Idaho," describes "border." However, when the compound adjective includes two-word parts, we use an en dash instead of a hyphen.

• A traffic jam is blocking the New York–Pennsylvania border.

Hyphen

The hyphen is the shortest of the three marks and can be found on the keyboard next to the number zero (0) and the equals sign (=). Hyphens can be used for three main purposes: to connect compound words and adjectives, to clarify certain prefixes, and to show word breaks.
Hyphens are used in most compound words and adjectives, but not in all compound words like phrasal verbs.

• mother-in-law, sugar-free candy, 5-year-old daughter
  but 
• Turn off the TV.
• The thief broke into my house.

Hyphens are used to clarify prefixes when the prefix might otherwise be ambiguous.

• co-owner (not "coowner")
• re-cover (to cover again) vs. recover (to get well)

Lastly, hyphens are used to show word breaks.

• Maria has two children: a five- and a three-year-old.
• Carsten is excited to start his uni-
  versity classes this week.

The em dash, the en dash, an the hyphen are three helpful punctuation marks. To learn more about punctuation and writing, visit us at Nomen Global.