Punctuaion Help

Punctuation! A brief guide to those tricky little marks.

Based on Lauren Kessler and Duncan McDonald. When Words Collide 4th ed. Belmont: Wadsworth Publishing Co., 1996.

Condensed by Wes Kisting

Definitions

To explain punctuation, I must use a few terms that may be unfamiliar to you:

• clause: a clause is a group of related words that contains a subject and a predicate.

• independent clause: an independent clause is a complete sentence. It expresses a complete thought.

• dependent clause: a dependent clause does not express a complete thought, and although it has both a subject and a predicate, it is not a complete sentence and cannot stand alone.

• coordinating/subordinating conjunction: basically, the words “and,” “but,” and “or.”

• non-restrictive: a type of clause, phrase, or modifier that is not necessary (not essential) in order to understand the sentence.

Comma (,)

Use a comma:

• to separate items in a series.

At the store, I bought oranges, apples, and pears.

• to separate two independent clauses connected by a coordinating conjunction, as long as the clauses don’t contain much internal punctuation (if they do, you might need to use a semicolon instead)

I’ve never needed the help of a forest ranger, but I hear they do help a lot of people.

• to set off a non-restrictive clause, phrase, or modifier (a comma goes before and after the non-essential information)

Tommy, the son of John Smith, is the first person I ever saw hit a home run.

• to set off parenthetical expressions (an expression that gives extra or not-so-crucial information in a quieter tone)

The goal of this class, as you ought to know, is to improve your writing and speaking skills.

• whenever the absence of a pause could cause confusion

Circling the factory, workers protested the unsafe working conditions.

• when a dependent clause introduces the sentence

Because I ate too much, I felt sick.

• to precede a quotation that is a full sentence

The manager asked, “Do you think the customer is always right?”

Do not use a comma:

• to introduce a dependent clause after an independent clause (in general, do not use a comma before the word “because”)

I felt sick, because I ate too much.

• to separate two independent clauses that are not joined by a coordinating conjunction.

The inflation rate dipped to 2 percent, the unemployment rate stayed constant.

(This mistake is called a comma splice, and you can correct it by adding a coordinating conjunction after the comma, or by replacing the comma with a semicolon or period.)

• when the comma will falsely make it seem like you are listing items in a series

The police found three dead bodies, two female victims and one male victim.

(In this example, a colon or dash should be used instead of the comma. That way it will be clear that the phrase “two female victims and one male victim” is describing the gender of the “three bodies” the police found. Otherwise, it might seem like the police found a total of six dead bodies.)

• to precede a partial quotation

The manager says the customer is, “always right.”

Semicolon (;)

Use a semicolon:

• to join independent clauses not connected by a coordinating conjunction

The inflation rate dipped to 2 percent; the unemployment rate stayed constant.

Note: the words “however,” “moreover,” “nevertheless,” and “therefore” are not coordinating conjunctions. When you use them,