A comma is such a little thing. However, by adding one or by not adding one, the entire meaning of a sentence can change.
Example: The prefab building shall include a control room, shift accommodations and training area.
If the vendor reads this specification, will it be clear as to whether there should be two rooms (one control room and one for shift accommodations and training) or three separate rooms?
Revision for three areas case:
The prefab building shall include a control room, shift accommodations, and a training area.
Revision for two rooms case:
The prefab building shall include a control room, as well as a shift accommodations and training area.
Now there is no confusion. See how a little comma is critical to the sentence?
The SPE Style Guide states: “In a series of three or more elements, use commas between each element and before the final conjunction.”
A, B, and C.
W, X, Y, or Z.
The key is to be consistent throughout your document in applying this rule, otherwise confusion such as happened in our first example will occur.
Here’s another example, sent in by a member of the Peanut Gallery:
An English professor wrote the following words in chalk on the blackboard:
(Remember those? Oops, there I go dating myself again. I’ve got to quit doing that!):
“A woman without her man is nothing”
The students were asked to supply the proper punctuation. All the boys in the class wrote:
“A woman, without her man, is nothing.”
All the girls in the class wrote:
“A woman: without her, man is nothing.”
You see? A comma can be a very powerful thing!