Are we allowed to insert serial commas before dependent clauses?
For instance, is the following sentence correct?
I am really serious this time out, and won't quit before the job is done.
won't quit before the job is done is a dependent clause, right? . . .
It is an independent clause with an implied subject, "I." At least it is if you use the comma. But without the comma, well, frankly I am not sure what one calls it, but the subject of both verbs (
am and
won't) is the pronoun I. (Simplifying the sentence:
"I am serious and won't quit.") Diagramming might help to illustrate.
In dialogue, to use or omit the comma reflects the writer's intent regarding how the sentence is spoken by the character--with or without the pause after "out." In other words, it would be the writer's call, and might be something to be argued with an editor.* I suspect that it might be better to insert the implied "I" so the sentence reads, "I am really serious this time out, and I won't quit before the job is done." But the comma would still be the writer's call as to whether or not there was a pause. If it is not dialogue, then the comma should be included.
My views, FWIW.
In any event, it is definitely
not a serial comma. That is a whole different issue. Here is a very simple example of a serial comma:
I went to the store and bought flour, sugar, and raisins.
The comma after "sugar" is the serial comma. Strunk & White and the
Chicago Manual of Style say to use it. AP says to omit it. Small wars have been fought over that dispute. But it is not the point you were actually raising.
*"In other words, it would be the writer's call, and might be something to be argued with an editor." The implied subject of "be" in the second part of the sentence is "it": "In other words, it would be the writer's call, and it might be something to be argued with an editor."
--Ken