Here are three recent questions from readers about the use of commas, along with my responses.
1. Can you tell me why there should be a comma in this sentence: “Such programs will also reduce operations costs and indemnity payments, and improve communications between employer and employee.” It seems like there shouldn’t be, because these aren’t two independent clauses.
It’s common for writers to insert a comma before a conjunction in a sentence when the conjunction does not begin a new clause but the phrases before and after it include their own conjunctions. This effort to make the sentence’s organization more obvious is not wrong, but it’s unnecessary.
The sentence structure becomes clearer if the first verb, the one that’s overworked in its efforts to support the entire sentence, is relieved by being repeated in a parallel position after the major conjunction: “Such programs will also reduce operations costs and indemnity payments and will improve communications between employer and employee.”
2. I saw this sentence in one of your posts lately: “It enables individuals and groups to meet online to collaborate, and to share presentations, applications, or their entire desktop, while increasing reliability and security and reducing costs.” Why is there a comma after collaborate?
The first comma in this sentence does not have the same function as the extraneous one in the previous example. It is the first in a pair of commas that mark a parenthetical. The phrase “and to share presentations, applications, or their entire desktop” may be omitted from the sentence, and the remaining statement will still be grammatically sound.
3. In “Our vision statement is a succinct way of explaining our purpose to others, be it our own staff, our residents or community clients or the wider public,” the two ors make it clunky to me. The or between “our residents” and “community clients” signals that the sentence is about to end, and then there’s another or! Should I have a comma in there somewhere?
If your style calls for serial commas (“a, b, and c”), insert a comma after clients: “Our vision statement is a succinct way of explaining our purpose to others, be it our own staff, our residents or community clients, or the wider public.”
If not (“a, b and c”), leave it as is. However, if that solution seems clumsy to you (I don’t find the final or confusing), separate “our residents or community clients” into two items: “Our vision statement is a succinct way of explaining our purpose to others, be it our own staff, our residents, our community clients or the wider public.” (Insert a comma after clients, or don’t, depending on whether you insert or omit serial commas.)