Grammar: To Comma or Not To Comma

After reading Cindy Davis's excellent You Have The Power on editing and reading the comma and adverb heavy Twilight, I am happy to finish this series on commas with an entree to colons and semi-colons.

In compound sentences with two independent clauses, a comma is used before connecting words like and, but, for, or, nor, so, yet.

Pride and Prejudice is one of my favorite Jane Austen stories, but it is difficult to choose which adaptation I like more.

The movie version of Pride and Prejudice released in 2005 is the most recent adaptation, and Keira Knightley was an excellent choice to play Elizabeth Bennett.

The lighting in the 2005 version is subdued and ethereal, yet captures a sense of magic and melancholy that is missing in a couple of the other versions.

It is a bit late to introduce the simple and common sense uses of the comma, as in dates and the separation of city, state and country. In a sentence, the month and day are separated from the year by a comma, but a comma is not used after the year unless it is the end of a phrase of clause.

August 29, 2009

August 29, 2009 is a Sunday and nearly the end of summer.

Colorado Springs, Colorado
New Orleans Parish, New Orleans, Louisiana
Eastbourne, England, UK

When two independent clauses are linked, a semi-colon is used instead of a comma. Two independent clauses are linked together when the subjects are connected.

The patient's CT scan was negative; fractures were found on a subsequent MRI.

The statue was carved as though the woman wore a veil; her face was obscured and the contours suggested rather than clearly defined.

The head of a female statue was found intact and well preserved in the ash and mud of Herculaneum; it was painted and the eyes were colorful and realistic.

When conjunctive adverbs, like however, moreover, therefore, consequently, otherwise, nevertheless, thus, etc., are used to connect independent clauses, a semi-colon is used. If the clause following the conjunctive adverb is a dependent clause, a comma is used.


Empty-eyed marble statues look ghoulish to me; however, ancient statues were used as models and historians and artists were unaware the statues had been originally painted.

Modern statues are very realistic; nevertheless, I often wonder what Michelangelo's David would look like painted in realistic colors.

I was enrolled in college courses on painting, sculpting and drawing during the summer between my freshman and sophomore years; consequently, I was exposed to more advanced techniques than the students in my high school art classes.

I doubt my mother would have approved had she known the subject of some of my classes, like sketching nude men and women, thus, my choice not to tell.

And that concludes the subject of commas. I hope you have learned as much as I have and found at least something to make you think or laugh. Next week, we push on with semi-colons and colons. Yes, Virginia, there is a difference. Until then, may all your grammar goofs be edited before they go to print.