The Ps and Qs of Ems and Ens
by Kristy Schnabel, MBA, It's Virtually Done

What is an em and en anyway? If you guessed a rap artist, you might be close to something, but I'm talking dashes in punctuation, not popular music. In short, an en dash looks like the hyphen (-) and the em dash is twice as long like two hyphens together (--). But how do you know when to use which?

Em Dash
Use the em dash in place of the comma, semicolon, colon, and parentheses. Examples:

Comma:

• Comma: "At the picnic, the food, and the weather, were great."

• Em dash: "At the picnic, the food--and the weather--were great."

Semicolon:

• Semicolon: "You set the table; I'll make dinner."

• Em dash: "You set the table--I'll make dinner."

Colon:

• Colon: "Keep this in mind: practice makes perfect."

• Em dash: "Keep this in mind--practice makes perfect."

Parentheses:

• Parentheses: "The salad dressing (creamy Italian) was fabulous."

• Em dash: "The salad dressing--creamy Italian--was fabulous."
  (Sabin, 1996)

It's important to remember that the dash is used for emphasis. Since it breaks up the flow of the sentence, only use the em dash to stress a point. Also note that there are no spaces on either side of the em dash.

Grammarians agree that the em dash is overused and should be used sparingly to create an effect. (Sabin, 1996; O'Conner 1996) When setting off parenthetical information in a sentence, Lois Johnson Rew in Editing for Writers created a hierarchy of emphasis:

• Strongest emphasis: use em dashes.

• Equal emphasis: use commas.

• Reduced emphasis: use parentheses.

En Dash
The en dash, on the other hand, is used in place of the word "to." For example, "Read pages 45-90 for your homework assignment." However, when a range of numbers is preceded with the words "from" or "between," don't use the en dash. Instead, use "to" or "and" as in, "We were the reigning champs from 1998 to 1999 and between 2000 and 2004. (Sabin, 1996)

Summary
Besides learning two new small words for Scrabble, you now know the difference between an em dash and an en dash. You'll do your English teacher proud if you know when to use your em dash for emphasis--and when to use another punctuation mark instead.

References:
O'Conner, Patricia T., Woe Is I, The Berkley Publishing Group, New York, 1996
Rew, Lois Johnson, Editing For Writers, Prentice-Hall, Inc., New Jersey, 1999.
Sabin, William A., The Gregg Reference Manual, Gencoe/McGraw-Hill, Ohio, 1996.