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Contributors:Tony Cimasko.
Summary:

These resources provides guidelines for using punctuation in your writing.

Punctuation

Although punctuation marks are small, punctuation takes on significant tasks:  separating ideas, relating ideas to one another, clarifying meanings, and indicating changes from one voice to another.  Without proper punctuation, readers can get confused and frustrated rather quickly.  The following is a brief guide to all the puncutation types you will encounter in English and activities designed to give you practice with each of them.

Sentence Punctuation

In formal and semi-formal English writing, the sentence is the smallest complete textual unit.  Aside from titles, anything less than a sentence (lacking an explicit or implicit noun or an explicit or implicit verb) is not acceptable.  Most sentences in English end with periods (.), while question sentences end with question marks (?), and sentences indicating very strong emotions or voice end with exclamation marks (!):

Questions and exclamations tend to be shorter than other sentences.  Although there are no hard and fast rules to follow for sentence length, it is a good idea to keep them from becoming “run-on” sentences.  If you do not limit the length, you risk confusing your audience.  If a sentence you have written is getting overly long (which is probably the case if there are a lot of other punctuation marks in the sentence, or a lot of information with no punctuation at all), break it down into smaller idea units and insert periods for each:

Without Correct Punctuation

Chiyoko is doing the presentation tomorrow, it will cover Reconstruction following the American Civil War, there were so many topics that we covered in the Civil War chapter that I don’t know how she was able to choose just one, and the presentation has to be less than twenty minutes!

With Correct Punctuation


Chiyoko is doing the presentation tomorrow.  It will cover Reconstruction following the American Civil War.  There were so many topics that we covered in the Civil War chapter that I don’t know how she was able to choose just one.  The presentation has to be less than twenty minutes!

Contributors:Tony Cimasko.
Summary:

These resources provides guidelines for using punctuation in your writing.

Punctuation—Commas

Although punctuation marks are small, punctuation takes on significant tasks:  separating ideas, relating ideas to one another, clarifying meanings, and indicating changes from one voice to another.  Without proper punctuation, readers can get confused and frustrated rather quickly.  The following is a brief guide to all the puncutation types you will encounter in English and activities designed to give you practice with each of them.

Sentence Punctuation

In formal and semi-formal English writing, the sentence is the smallest complete textual unit.  Aside from titles, anything less than a sentence (lacking an explicit or implicit noun or an explicit or implicit verb) is not acceptable.  Most sentences in English end with periods (.), while question sentences end with question marks (?), and sentences indicating very strong emotions or voice end with exclamation marks (!):

Questions and exclamations tend to be shorter than other sentences.  Although there are no hard and fast rules to follow for sentence length, it is a good idea to keep them from becoming “run-on” sentences.  If you do not limit the length, you risk confusing your audience.  If a sentence you have written is getting overly long (which is probably the case if there are a lot of other punctuation marks in the sentence, or a lot of information with no punctuation at all), break it down into smaller idea units and insert periods for each:

Without Correct Punctuation

Chiyoko is doing the presentation tomorrow, it will cover Reconstruction following the American Civil War, there were so many topics that we covered in the Civil War chapter that I don’t know how she was able to choose just one, and the presentation has to be less than twenty minutes!

With Correct Punctuation


Chiyoko is doing the presentation tomorrow.  It will cover Reconstruction following the American Civil War.  There were so many topics that we covered in the Civil War chapter that I don’t know how she was able to choose just one.  The presentation has to be less than twenty minutes!

Commas

Commas are perhaps the second most important punctuation mark to master, after periods.  They are used to separate pieces of written text that are not adequate as full sentences by themselves.  These pieces can be introductory words and phrases, dependent clauses, adjectives, or items in a list:

Commas are also used for independent clauses that could grammatically stand as independent sentences, but are too short for academic or professional writing to be sentences on their own and are separated by a conjunction (for, and, nor, but, or, yet, so):

Commas are also used to separate quoted material from text you have written yourself:

Finally, commas are used in the American style of writing calendar dates, and before a series of three digits in longer numbers (excluding years and decimals):

Quick Guide to Commas

1. Use commas to separate independent clauses when they are joined by any of these seven coordinating conjunctions: and, but, for, or, nor, so, yet.

2. Use commas after introductory a) clauses, b) phrases, or c) words that come before the main clause.

3. Use a pair of commas in the middle of a sentence to set off clauses, phrases, and words that are not essential to the meaning of the sentence. Use one comma before to indicate the beginning of the pause and one at the end to indicate the end of the pause.

4. Do not use commas to set off essential elements of the sentence, such as clauses beginning with that (relative clauses). That clauses after nouns are always essential. That clauses following a verb expressing mental action are always essential.

5. Use commas to separate three or more words, phrases, or clauses written in a series.

6. Use commas to separate two or more coordinate adjectives that describe the same noun. Be sure never to add an extra comma between the final adjective and the noun itself or to use commas with non-coordinate adjectives.

7. Use a comma near the end of a sentence to separate contrasted coordinate elements or to indicate a distinct pause or shift.

8. Use commas to set off phrases at the end of the sentence that refer back to the beginning or middle of the sentence. Such phrases are free modifiers that can be placed anywhere in the sentence without causing confusion.

9. Use commas to set off all geographical names, items in dates (except the month and day), addresses (except the street number and name), and titles in names.

10. Use a comma to shift between the main discourse and a quotation.

11. Use commas wherever necessary to prevent possible confusion or misreading.

Contributors:Tony Cimasko.
Summary:

These resources provides guidelines for using punctuation in your writing.

Punctuation—Quotation Marks and Apostrophes

Quotation marks (") are often used to indicate something said or written by another person, particularly if it is included inside your own original writing.  If the quotation is embedded inside one of your own sentences, use commas, as shown in the following.

Quotation marks are also used for language used to describe something or someone, but which is not being used by most people.  Some examples include nicknames, labels for things that people do not wish to talk about in detail, or new things that have not been named or identified yet:

As you can see in the examples above, when a comma or period comes at the end of a pair of quotation marks, it goes inside the marks, not outside.  However, if you are using quotation marks for a special word or phrase (not quoting someone’s writing or speech), you can put question marks and exclamation marks outside the quotation:

Apostrophes (') are used less frequently in American English writing.  They are used with an s to indicate possession by one person or thing ('s) or two or more persons or things (s'):

They are also a necessary part of contractions, in which words are combined or shortened:

Contributors:Tony Cimasko.
Summary:

These resources provides guidelines for using punctuation in your writing.

Punctuation—Semicolons, Colons, and Parentheses

A number of other punctuation marks are used less frequently, but still play important roles in English writing.  Semicolons (;) are used to combine sentences into larger ones.  Unlike the use of commas to combine very short sentences, semicolons are used for combining relatively longer sentences.  Semicolons are often used for combining sentences that are very closely related:

Colons (:) are used at the beginning of lists of several or more items, or as a substitute for “it is, “they are,” or similar expressions:

Parentheses () are used to say something that is important to the main message you are writing but is not an immediate part of it, something that would interrupt the flow of your writing if you didn’t keep it separate from everything else:

Contributors:Tony Cimasko.
Summary:

These resources provides guidelines for using punctuation in your writing.

Punctuation—Hyphens and Dashes

Hyphens (-) are used to connect two or more words (and numbers) into a single concept, especially for building adjectives.  Likewise, some married women use hyphens to combine their maiden name with their spouse’s name:

They are also a necessary component of the numbers 21 through 99:

Although they can be used as substitutes for the word “to” when discussing value ranges and scores in games, it is better to use the word in formal writing situations than the punctuation:

Hyphens are also used in syllable breaks when words cannot fit completely on a line, and must be continued on the following line.  With word processors and the ability to automatically move whole words, though, this has become less common:

Dashes (—) can be used to indicate an interruption, particularly in transcribed speech:
The chemistry student began to say, “An organic solvent will only work with—” when her cell phone rang. 

They can also be used as a substitute for “it is, “they are,” or similar expressions.  In this way they function like colons, but are not used for lists of multiple items, and are used less frequently in formal writing situations:

They can also be used as substitutes for parentheses:

Note that dashes are double the length of hyphens.  When you type two hyphens together (--), most word processors automatically combine them into a single dash.
The Purdue OWL maintains a number of resources on punctuation you can visit to learn more: