Business Writing Essentials
Quotation marks are used to mark three things: exact words said, special emphasis, and titles of literary things. At work, you will be concerned primarily with the first two.
Exact words said
Direct quotations specify the exact words that were said, and should use quotation marks:
Ann asked, "Who will be in charge?"
Direct questions, that are not quotations of words actually spoken, should not use quotation marks:
The question is, Who will be in charge?
Indirect quotations (rephrasing) should not use quotation marks:
Amy asked whether anyone will be in charge.
Avoid using quotation marks for the words yes and no, unless you want to emphasize that they were the exact words spoken:
You need to start saying no to special requests.
Ben responded with a definite "no" to that request.
Note: If a direct quotation goes to the end of a sentence, the sentence's ending punctuation typically goes inside the final quotation mark. But it can be complicated, so when in doubt look it up. (once again, The Gregg Reference Manual)
Words or phrases that are unlikely to be understood by the reader can use quotation marks:
Whatever you do, don't press the "esc" key.
Words used in an untypical way can use quotation marks:
We are selling the machine on an "as is" basis.
[or with italics, as-is, without quotes]
Special phrases that are commonly used do not need quotation marks:
Bob explained the whys and the wherefores.
Course: Business Writing Essentials