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Writing: Style & Grammar

This Guide was created as a joint project of the Academic Resource Center and the William H. Hannon Library. It is being used here with permission from ARC.

Directed Learning: Commas and Colons

Woman, without her, man is nothing. Woman, without her man, is nothing.


Commas do make a difference!

Most people have trouble with commas, semi-colons, and colons. The best way to remember when to use which one is how long of a pause you plan to take: commas being the shortest pause, periods the longest pause. For those looking for hard-fast, definitive rules, here are some useful guidelines for pesky punctuation.

COMMAS

After introductory clauses, phrases, or words that come before the main clause.

  • Before Sean ordered tickets online, he needed to know how much they cost.
  • At the lobby’s busy refreshment counter, Sean waited for his salted pretzel and licorice. 
  • Fortunately, his date didn’t want anything to eat because she was watching her weight.

Use commas between items in a list.

  • Sean and his date turned their cell-phones off as the lights dimmed, the house music ended, and the previews started.

Separate adjectives that are equal and reversible.

  • A mother removed her irritable, fidgety child from the theater.

Separate the clauses of a compound sentence with a comma before the coordinating conjunctions (FANBOYS: forandnorbutoryetso).

  • Sean’s date asked to change seats because a kid with a really big forehead was kicking her chair, so they moved up a row.

Nonessential words, phrases, or clauses must be set off with commas. Think of the information within the commas as not crucial to understanding the sentence. Also, transitional words within a sentence like howeverthereforethenconsequentlybesidesindeedlikewise, etc. are set off by a comma on both sides.

  • Pixar’s Toy Story 3, the movie that they went to see, was an animation delight.
  • Woody and Buzz, the main characters, are heroes to children everywhere.

SEMICOLONS

Use a semicolon between two sentences that are closely linked.

  • Sean really enjoyed his date’s company; she was both funny and beautiful.

Before transitional words such as howeverthereforeneverthelessfor exampleas a result and a comma after when there is an independent clause on both sides of these words.

  • She laughed uproariously during the movie; however, Sean didn’t seem to mind at all.

In place of a comma to separate items in a series when the items already contain commas or when the items are long.

  • Sean then met her family: her dad, who came from New Zealand; her mom, who likes underwater basket-weaving; and her brother, who has oddly shaped feet.

COLONS

The purpose of a colon is to introduce, define, or clarify something. Although a colon can be used either between two independent clauses (sentences) or between an independent and a dependent clause, it can follow only the independent clause; it may never follow a sentence fragment.

Use a colon when a second independent clause elaborates on the first one.

  • He checked the temperature: it was 100 degrees.

Use a colon to introduce a list or a quotation.

  • I enjoy creative hobbies: painting, writing, and singing.
  • She said the awful words: “I got you one just like it!”

Directed Learning Activity: Commas and Colons

Links to Other Resources