The Uses of An Exclamation Point (!)

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The exclamation point ( !) is a terminal punctuation mark in English and is usually used at the end of a sentence with no extra period. It can turn a simple indicative or declarative sentence into a strong command or reflect an emotional outburst. It can also indicate rhetorical questions. Do not use an exclamation point in texts that are neither literary dialog nor personal expressive writing. It is inappropriate to put an exclamation point in formal pieces of writing such as a business resume, school book report, or a due college paper, as the style expected in these should be objective, standard, and informative. Using an exclamation point in such settings creates an impression of unwarranted exaggeration, which in turn is perceived as amateurish, marketing oriented or just plainly childish. Do use it in stories and personal communication, and even then, sparingly.

Using an exclamation point for indicating a strong emotion or emphatic declaration

1. In dialogue, use the exclamation point to indicate a strong command in an imperative sentence. This denotes a firm and direct order.

Clean the elephant enclosure now!
Look out, there's an elephant running behind you!

2. In dialogue, use the exclamation point to convey an emphatic declaration, which can indicate any of the following emotions:

Shock: "There's been a terrible accident!"
Excitement: "Oh my God! What a fantastic birthday gift!"
Urgency: "Drive carefully! Watch out for traffic signs! If you don't, you could die!
Vehemence:"Down with the new anti-elephant laws!"
Astonishment:"I just can't believe what she's done! It's simply beyond me!"

3. Even in literary or dialog writing, over-use of the exclamation point should be avoided, using alternative wording or other punctuation marks to express emotion. Experienced writers know how to make their readers infer emotions from context.
Avoid: The Japanese food at Kyoto was just out of this world!!! Super-duper!!! These guys know how to cook!
[Exaggerated enthusiasm using too many exclamation points]

Consider: The Japanese food at Kyoto was the best we have ever had. It appears that the chefs there are highly professional.
[Subtle enthusiasm using alternative wording with periods instead of exclamation points]

Pay attention!

4. Do not use the exclamation point with a period, comma, colon, or semicolon.

No: He shouted: "Watch out!."
No: "Watch out!," he shouted.
Yes:"Watch out!" he shouted.

5. Do not use the exclamation point to express overt amazement or sarcasm. Use other words for rephrasing. At 3.3 meters and 7 tons (!), the African elephant is the biggest (!) land animal on Earth. Yet, Johnny (!) thinks     that the Indian elephant is bigger.
[1st exclamation point expresses amazement, 2nd exclamation point expresses sarcasm]

At a majestic 3.3 meters and 7 tons, the African elephant is the largest land animal on Earth. Yet, Johnny,         stubbornly, thinks that the Indian elephant is larger.
[majestic expresses amazement, stubbornly expresses sarcasm, both instead of the exclamation point].

6. "In was back again, a hopeless cripple." literary prose or poetry, an exclamation point is sometimes seen in the middle of sentences, where it need not be followed by a capital letter. See also the exclamation point style conventions below.
"Two years earlier, I had walked off into the sunset – cured! It’s a miracle! She can walk! And now I
     Nora Ephron, Heartburn

Using an exclamation point for indicating rhetorical questions

Check this out!

Aren't his paintings amazing? [interested or surprised reaction]
Aren't his paintings amazing. [uninterested or musing reaction]
Aren't his paintings amazing! [indignant or exciting reaction]

Analysis ! When the above rhetorical question is used with different punctuation marks, the rhetoric implication is altered (as shown in the brackets). This demonstrates the emotional effect punctuation marks may have in a text.
If you want to know more, read the punctuation rules below

The Punctuation Rules for Using an Exclamation Point in Rhetorical Questions:

1. A rhetorical question is a question for which no answer is expected or for which the answer is self-evident. A rhetorical question can end in either a question mark, or an exclamation point or a period, depending on context and the writer's purpose.
I did everything I could for that company; do you think they thanked me?
[apparently not]

How can I ever thank you enough!
[obviously you will have to work hard thanking]

How could I have known that those documents I had sent were top secret.
[You couldn't have]

2. An exclamation point at the end of a sentence can create the following effects:
Do you really believe I can read all these books about elephants by tomorrow!
[disgruntlement]

Aren't the twins adorable!
[wonder and awe]

Is there any way on this earth I can ever get my father's approval !
[despair]

3. Rhetorical questions in a dialog are better ended with a period, as this imparts a more realistic tone.

"Look, why don't we just forget about this deal."
"Well, isn't that what I expected to hear."

4. You can use an exclamation point with italics to show shock or incredulity.
She said what!

Using an exclamation point for drawing attention to unlikely points

1. Writers sometime like to sparingly use an exclamation point enclosed in parenthesis to draw the reader's attention to unlikely, ironic or unexpected sentences. However, it may be more elegant to choose different wordings to express irony and such.
After his 98th (!) hot dog, Abner Manishewitz won first place in the L.A. County eat-offs.
[Exclamation point expresses amazement and maybe also disgust]

After his hard to believe and visually disturbing 98th hot dog, Abner Manishewitz won first place in the L.A. County eat-offs.
[his hard to believe and visually disturbing expresses amazement and maybe also disgust]

Exclamation point style conventions

1. Do not use a comma after an exclamation point occurring in the middle of a sentence.
"You didn't do everything I asked!" her boss said angrily.

2. Do not use a period after an exclamation point occurring in the end of a sentence, even if followed by quotation marks.
Her editor always likes to say, "This writer is on the verge of a nervous breakdown!" It always makes me laugh.

3. You can use an exclamation point with other visual emphasizes, such as capital letters, boldface or italic type (again, this should be done sparingly)
"You didn't actually agree to that offer!" her boss asked incredulously.

4. When an exclamation point follows a quoted text, put it before the closing quotation mark if it applies just to the quoted text. Put the exclamation point outside the closing quotation mark if it applies to the entire sentence.
If only I could finally say "I've graduated from college" like all my friends!
[entire sentence is exclamatory]

"I've graduated from college !" cried Dan to his grandmother excitedly on the phone.
[only quoted text is in exclamatory, no extra comma after an exclamation mark]

5. When an exclamation point is used with parenthesis, put it inside the parenthesis if only the enclosed text is exclamatory. When the whole sentence is exclamatory, put the exclamation mark outside the parenthesis. If the text enclosed in the parenthesis is a stand alone sentence, add the appropriate terminal punctuation mark. Always put a terminal punctuation point at the end of the sentence, regardless of what punctuation mark appears in the parenthesis.
For months, I stayed in extra hours to complete the project (I couldn't bear it!).
[exclamation point inside the parenthesis, only enclosed text is exclamatory]

It's just not fair that Dan has to work over time (despite being denied of a promotion)!
[exclamation point outside the parenthesis, whole sentence is exclamatory]

6. When an exclamation point immediately follows an italicized text, italicize it as well.
You're kidding, he promoted her!