Writing & Grammar Workshop: The Long Dash—Know It and Love It!

The long dash, or em dash, is a piece of sentence punctuation that only editors seem to fully understand, yet everyone wants to use one.  Some writers use a dash when they just don't know what other punctuation to use. In fact, the flexibility of guidelines for dashes encourages this use, because the em dash has several possible meanings. Knowing the meanings of the dash will give you a powerful piece of punctuation to add flexibility to your sentences.

 

One meaning of the dash is the same meaning as a colon: I have introduced something, and the thing I introduced follows. The only difference between using a colon and using a dash to introduce something is that a colon requires a complete sentence before it, whereas a dash does not.

 

We listened to three songs:

We listened to—

The dash in the second list indicates that each item on the list completes the sentence. A dash can also introduce a surprising or emphatic ending on a sentence:

At the end of the set he played one last song—then came back for three more encores!

A pair of dashes can be used to set off an interruption in the middle of a sentence. Of course an interruption could be punctuated with parentheses or a pair of commas. The dashes indicate more of an abrupt and unexpected interruption that might actually be more interesting or important than the sentence itself. Here are examples:

• The first song of the set, we all agreed, was by far the best. [ordinary interruption]
• Stevie Ray Vaughan—he played several major gigs with Albert King—is featured on this album. [important and very interesting interruption]
• The instruments—including the original strat used by Stevie on Texas Flood—are stored in a warehouse. [another important and very interesting interruption]

These three uses—to introduce a list, to introduce an emphatic or interesting end to a sentence, and to set off important or interesting interruptions—make the dash a very convenient punctuation mark to know—and love.