Punctuate. Punctuate? Punctuate!

You might be surprised to learn that you're not the only one who has trouble with punctuation. Most of my students do.

Everyone knows that a period ends sentences that are not questions, such as:

It was a moonlit night.

However, some students make the mistake of putting a period at the end of a sentence that is a question, such as:

Was it a moonlit night?

Here is a quick reference guide to common punctuation marks.

PERIOD ( . ) -- ends sentences that are not questions.
It was time for me to leave.

QUESTION MARK (?) -- ends sentences that are questions.
Is it time to leave?

COMMA ( , ) --tells the reader to pause slightly, and it helps differentiate the parts of a sentence. The comma is by far the most misused punctuation mark, probably because it can be used in so many different situations. Use a comma in the following conditions:

Following an introductory phrase: After a week of record heat, the temperature dropped nearly to the freezing point.

To separate items in a series: I love Las Vegas for its sun, fun, and amazing desert landscapes.

Before a coordinating conjunction that connects two independent clauses: She believed he would ask her to go to the beach, and he did.

To set off nonrestrictive phrases (parenthetical phrases that add to a sentence but aren't absolutely necessary for the sentence to make sense.): The car, which I had bought from a crooked dealer, broke down so often I soon knew the bus schedule by heart.

To set off quotations contained within a sentence: "I don't like hip-hop," he pointed out, "so I don't like to go clubbing with them."
My boss said, "It's time to put the hammer down," so I made ten extra sales calls this afternoon.

To indicate direct address: "Joe, make sure your room is spotless."

To separate distinct adjectives in a series: The loud, constant, reverberating noise of the city makes me crazy.

In a date, between the day and year: On September 11, 2001, the world as we knew it changed forever.

To indicate the omission of verbs in parallel clauses: Abe loves the drums; Sally, the guitar; and Jo, the piano.

EXCLAMATION MARK ( ! ) -- to end declarative and imperative sentences with excitement or urgency. Show me the money!

COLON (:) -- introduces a list of things, a summary, or an important conclusion. The colon is used after an independent clause and does not come between a verb and its object.
I expect my students to do three things: listen, share, and learn.
Arturo learned one very important lesson: Never trust an ex-girlfriend's movie recommendation.

SEMICOLON (;) -- used to join related independent clauses in place of a conjunction (and, or, nor, but, etc.). Semicolons are also used to separate items in series that contain commas within single-item descriptions. Suki likes to make Chinese food; it is her passion.
He had a brand new Mac; an old desktop PC; and an ancient manual typewriter.

QUOTATION MARKS (" ") have many uses:
To represent text as speech: "I could have been a contender," he sadly admitted.
To indicate material taken from another source: The artist's work shows "the agony and the ecstasy" of the creative process.
To indicate titles of poems and short stories: The old man in Ernest Hemingway's "A Clean, Well-Lighted Place" is having a crisis of faith.
Please note: Periods and commas always go inside quotation marks in American English. Question marks, exclamation marks, semicolons, colons, and dashes go outside quotation marks unless they are part of the quotation. (This isn't true for written English in Great Britain.)

DASH (--) -- sets off a parenthetical phrase or draws attention to a final conclusion. The IPod--introduced only a few years ago--has become the most popular portable music player.
His hair, his eyes, his taste in clothes--they all are perfect.

APOSTROPHE ( ' ) -- used to indicate possession when combined with a noun. An apostrophe also signals that one or more letters have been left out in a contraction. Maureen's tomcat is one mean critter.
Where there's a will, there's a way.
I don't like vegetarian cooking.

HYPHEN (-) --joins linked words together, especially if they are used together as an adjective:
He never could kick his desire for fresh-made ice cream.

PARENTHESES ( ) -- used to set off a loosely related phrase: His new goal (conceived after he was fired for no good reason) was to start his own business.

SLASH (/) -- indicates multiple possibilities: Tell the teacher and/or the principal.

ELLIPSIS ( ... ) -- three periods separated by two spaces that mean some quoted material has been omitted, usually for brevity's sake: A great philosopher once wrote, "The Gods had condemned Sisyphus ... to become the futile laborer of the underworld."

BRACKETS ( [ ] ) -- indicate any word, punctuation, or formatting inserted into a quote but not present in the original source: "The racers have one mile [1.6 kilometers] to go before the finish line."