The Big Bad Three of Punctuation: The Comma, Semicolon and Colon

Punctuation adds clarity and makes your writing easier to read. 

There are several types of punctuation that can be used to create a pause or break in your writing: 14 to be exact! 

Three are used more commonly used than all the others, particularly in professional writing. 

Follow these easy rules to determine whether you need a comma, semicolon or colon in your writing.

Rules for using commas in your writing

Because they have so many uses, commas are one of the most frequently used punctuation marks. 

• To separate independent clauses joined by a conjunction. 

  The coordinating conjunctions are but, and, so, for, nor, yet, and or. Place the comma before the conjunction

  The roommates had always been friends, but their pets were still getting to know each other.

  I needed to talk to the boss, but she was in a meeting.

• To set off the nonrestrictive element in a sentence

  I gave the approval letter to Jean, the woman with the long hair, on the third floor.

• After an introductory phrase

  Because Jason owed Bob a favor, he offered to work the late shift for this this week.

• To set off conjunctive adverbs and adverbial phrase

  I went to the door to see him; he turned, however, and walked away.

  The Toledo office, on the other hand, is doing great.

A common argument among editors and writers is the use of the Oxford comma. Otherwise known as a serial comma, it's the last comma used in a list of three or more items. It's grammatically optional, but using it can help avoid confusion. For example, this passage from a newspaper article went viral on social media:

Among those interviewed were Merle Haggard's two ex-wives, Kris Kristofferson and Robert Duvall.

The intention here is to list three people who were interviewed; instead it sounds like Kristofferson and Duvall were Merle Haggard's ex-wives. However, if you're listing things that are clearly separate from one another, it's okay to omit the serial comma.

We visited France, Italy and Spain.

Rules for using semicolons in your writing

• To separate two closely related ideas that are not joined by a coordinating conjunction (and)

  I invited the Douglas family; I left the Johnsons off the list.

• To set off items in a list when one or more items in that list contain commas

  Francis brought bagels with raisins, walnuts and cranberries; six pints of coffee; four bags of cinnamon twists, complete with frosting; and a dozen doughnuts.

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Rules for using colons in your writing

• To introduce a list

  There are several things we still need: four reams of paper, six packs of strapping tape, three box cutters, eight balls of twine and two red markers.

• To illustrate or explain an idea

  Michelle knew what she had to do: apologize.

• After the salutation in formal correspondence

  To the Office of Transportation:

A final note on these types of punctuation: for it to be effective, use it sparingly. A sentence filled with commas or semicolons will be choppy and hard to read.