Regular readers realize that I often rant about outmoded or irrelevant traditional grammar rules in the contemporary workplace. So, it might surprise you that I’d even know punctuation guidelines, let alone share them with readers. Will wonders never cease? That all said, get to know your little friend, the comma – when to use it and how to use it.
1. In a Series – Use a comma after each item in a series, except the last. Examples:
“Please order paper clips, staples, markers and tape by Friday.”
“I need your meeting notes, a copy of the project charter and financial projections.
2. With Multiple Adjectives – Use a comma after each adjective, but omit the last comma if the last adjective acts as a unity with the noun. Examples:
“She has several large, expensive file cabinets in her office.”
“The stressful, demanding schedule led to his heart attack.”
3. With Independent Clauses – Use a comma before “and, but, for, nor, so or yet” when linking two clauses unless they are both closely related and short. Examples:
“I warned them about being late, but they didn’t care.”
“Costs are increasing, and the new project will reflect this trend.
4. After Introductory Clauses – Use a comma after an introductory phrase or adverbial clause and after an introductory subordinate clause. Omit the comma after short prepositional phrases. Examples:
“To appreciate the technical requirements, you must understand the project.”
“Since his projects were successful, he was promoted.”
“System throughput is down, although we expect it to increase in the fall.”
5. Before Coordinating Conjunctions – Use a comma before a coordinating conjunction (but, and, for, or nor) that links two independent clauses. Omit the comma between two short independent clauses. Examples:
“It rained all night, but it didn’t keep me from leaving the building.”
“She worked yesterday, and she showed him how to use the scanner.”
“I finished and I quit.”
6. Nonrestrictive Phrase or Clause – Use a comma to set off a nonrestrictive phrase or clause which adds non-essential descriptive information to a sentence. Examples:
“My manager, who has been in our department, decided to retire.”
“The engineers, who are in China, were involved.”
7. Appositives – Use commas to set off an appositive phase. Examples:
“The group listened to team leader, the former CFO, on financial planning.”
“The session facilitator, manager of operations, spoke to the group.”
8. Parenthetical Expressions – Use commas to set off parenthetical expressions – words or phases that interrupt the sentence with additional information. Examples:
“He felt, however, that the estimate was fair.”
“My manager, who happens to be an accountant, is fastidious.”
“We are, according to the audit, 30% over budget and its only first quarter!”
“It is, as I said before, a problem for both groups.”
9. Others Uses
a. Use a comma after no or yes if they begin a sentence. Examples:
“Yes, she did achieve her objectives.”
“No, I cannot help you.”
b. Use a comma when listing a complete date, but not just month and year. Examples:
“We must finish the job by December 1, 2013, to stay on schedule.”
“We’ll be done in December 2003.”
c. Use a comma with cities and states. Example:
“Our office in Miami, Florida, will be closed for renovation.”
d. Use a comma between contrasting elements. Examples:
“We need more quality control, not less.”
“Analysts must have common sense, not just a theoretical knowledge.”