APPENDICES: Academic Writing Basics
Appendix F: Punctuation Matters
Suzan Last
“Punctuation marks are the road signs placed along the highway of our communication, to control speeds, provide directions and prevent head-on collisions.”
Pico Iyer, “In praise of the humble comma”[1]
Punctuation Really Matters!
Consider how punctuation can change the meaning of the following run-on sentence:
I have two hours to kill someone come see me.
The main function of punctuation is to separate phrases and clauses into meaningful units of information. Therefore, it is necessary to understand the basic structure of sentences—phrases and clauses—to understand the proper uses of punctuation. When punctuation is missing or incorrectly used, the reader may get a completely different message than the one intended. This can not only confuse readers and waste time, but can have disastrous results in cases where the writing has legal, economic, or safety implications.
An example of how a punctuation error can have real world costs and consequences is reported in “Comma Quirk Irks Rogers”: one comma error in a 10-page contract cost Rogers $2 million.[3] If you need further evidence, read about the case of the trucker’s comma that went all the way to the supreme court, resulting in a $10 million dollar payout![4]
There are several helpful rules that will help you determine where and how to use punctuation, but first, it might be helpful to understand the origins. Punctuation was initially developed to help people who were giving speeches or reading aloud. Various kinds of punctuation indicated when and for how long the reader should pause between phrases, clauses, and sentences:
Comma = 1 second pause
Semicolon = 2 second pause
Colon = 3 second pause
Period = 4 second pause
These “pause rules” can still offer some guidance, but they are not foolproof, as there are many reasons that someone might pause while speaking, including that they simply ran out of breath, got distracted, or need time to think of a word. Below are some more consistent rules that you should follow to properly punctuate your sentences. These are presented in a numerical order to help you remember the rules more easily.
As we have discussed before, sentences are most often strongest when the subject is the first element of the sentence: S → V → O
Occasionally, however, we might want to place a word or phrase before the subject. In cases where you want to do this, it can be helpful, and often necessary, to place a comma after that word or phrase to clearly indicate the subject of the sentence. In the following sentence, see if you can determine what the subject is without a comma to help you:
Based on that initial design concepts will be generated.
The subject—and therefore the meaning of the sentence—depends on where you place the comma. If the initial phrase is “Based on that,” and “that” refers to some previously stated idea, then the sentence indicates that the subject is “initial design concepts,”