Dr Paul Carvey, distinguished professor of pharmacology in Chicago, writes:
I have been editing a lot of manuscripts, theses, dissertations, and term papers of late and have come across a common error made by our students involving the use of quotes and punctuation.
Commas and periods almost invariably go inside the quotes, yet half the material I have read places the commas and periods outside of the quotes.
I searched the Internet and looked at several writing guides, and all place the periods and commas inside the quotes. Exclamation and question marks generally go inside the quotes as well, but it can depend on context in some cases. Colons and semicolons generally go outside of quotes.
The only time a period goes after a quote is when a citation follows the sentence (e.g., ….these results were found” (24).
Paul M. Carvey, PhD
Dean, Graduate College
Associate Dean of the Basic Sciences, Rush Medical College
The Deborah R. and Edgar D. Jannotta Presidential Professor of Pharmacology and Neuroscience
Thank you, Dr. Carvey!
Writers can learn more at the Purdue OWL (see item #5 especially). Note, too, that the rule above applies to U.S. English. British English, especially from the previous century, follows different rules for quotation. Currently the Concise Oxford English Dictionary, 11th edition, puts the comma before the end-quote, but it uses a single quote (') where U.S. English uses a double quotation mark.
