Dashes or Parentheses?

by Cherie Tucker

Both parentheses and dashes show readers that you have interrupted the train of thought to tell them something right now.  They have more drama than mere commas, but they must be handled correctly to work.   Let’s take them one at a time.
 
Parentheses offer non-essential information that is like a whispered aside to inform the reader at that precise moment something the reader may not know. 

We’re bringing Julie (my brother’s latest girlfriend), so there will be four of us.

For parenthetical information that is not a complete sentence or comes at the end of the sentence, put the end punctuation after the end parenthesis.

There will be one more of us (my brother’s newest girlfriend).

If the parenthetical item that ends a sentence is short and requires its own punctuation, do this:  There will be four of us (yes, another new girlfriend!).  The exclamation mark punctuates the parenthetical item, while the period punctuates the whole sentence.  

Now let’s look at the dash. If parentheses whisper, the dash shouts.  It is an emphatic interruption for both essential and nonessential interruptions.

We will be four—yes, another new girlfriend—at your party.

As with parentheses, do not put a comma before the opening dash, and use internal end punctuation within the interruption if appropriate: We’re bringing Julie—have you met her?—so we’ll be four.  If the item in the dashes ends the sentence, replace the closing dash with the appropriate end punctuation: There will be four of us—another new girlfriend for my brother. By the way, for a dash, type two hyphens with no spaces before, after, or in between.  No floating hyphens, please. (Or use an em dash, also with no spaces before or after.)

Dashes should be used sparingly, lest like the over-used exclamation point, their impact is diluted. Yes, I know, Emily Dickenson used dashes throughout her poems, but remember, she never intended to be published.  

Cherie Tucker, owner of GrammarWorks, has taught writing basics to professionals since 1987, presenting at the PNWA conference.  She currently teaches Practical Grammar for Editors at the University of Washington’s Editing Certification program and edits as well.  GrammarWorks@msn.com