Punctuation: Period, Question Mark, Exclamation Mark: The End of the Line

Period, Question Mark, Exclamation Mark: The End of the Line

The period, question mark, and exclamation mark are the Three Musketeers of punctuation: all for one and one for all. Here's why:

  • They are all end marks; that is, they are used at the end of a sentence.
  • All three marks of punctuation have the same function: to indicate a full stop.
  • They all show the end of a complete thought.
  • They can all prevent run-on sentences.

Okay, so maybe they're not the Three Musketeers, but at least they're not the Three Stooges, Three Amigos, or the Three Bears. Let's look at these three end marks more closely.

The Period: Do Not Pass Go, Do Not Collect $200

The period is the workhorse of punctuation. Like a great dessert, it's always welcome at the end. Here's how to use periods:

  • Use a period after a complete sentence.
  • Example: A hangover is the wrath of grapes.
  • Use a period after a command.
  • Example: Please close the door behind you.
  • Use a period after most abbreviations.
  • Examples: Dr., Ms., Jr.
  • Don't use a period after the individual letters in an acronym. For example, write NATO, not N.A.T.O.
  • Use a period after an initial.
  • Example: John F. Kennedy
  • Use a period after each Roman numeral, letter, or number in an outline.
Example: I.
  • Always place a period inside a quotation mark that ends a sentence.
  • Example: The sign read, “A pest is a friend in need.”
Danger, Will Robinson

If an abbreviation comes at the end of a sentence, do not add another period.

The Question Mark: Inquiring Minds Want to Know

You know the rules for life: Never wear white shoes after Labor Day, brush after every meal, and avoid making rude noises in public. Here, then, are the rules for using question marks.

  • Use a question mark after a question.
  • Example: Isn't the Mason-Dixon line what separates y'all from youse guys?
  • Place the question mark inside of closing quotation marks if it is part of the quotation.
  • Example: In a dream, I heard someone asking, “Isn't atheism a nonprophet organization?”
  • Place the question mark outside of the closing quotation marks if it is not part of the quotation.
  • Example: Was it your mother who said, “The Lord prefers common-looking people; that's the reason he made so many of them”? (In such a circumstance, it's okay to drop the period from the quotation.)
Danger, Will Robinson

Do not combine an exclamation mark with a period, comma, or question mark.

Exclamation Marks: Gosh and Golly!

In speech, exclamations are used freely, especially in moments of high passion, as when the dishwasher overflows at 11 P.M. on a Saturday night. In writing, however, it is far more convincing to create emphasis by the force of your words rather than the force of your punctuation. But there will be occasions to use exclamation marks, so here are some guidelines to follow.

  • Use an exclamation mark after an exclamatory sentence.
  • Example: “Apparent” is a large, old bossy person who tortures youth!
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Excerpted from The Complete Idiot's Guide to Grammar and Style © 2003 by Laurie E. Rozakis, Ph.D.. All rights reserved including the right of reproduction in whole or in part in any form. Used by arrangement with Alpha Books, a member of Penguin Group (USA) Inc.

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