In writing, the correct and consistent use of punctuation marks can aid clarity and comprehension among readers--enhancing a reader's relationship with the writer. Using those marks is good writing etiquette. Those marks are also like traffic signs for following the rules of the road. When readers see them, they know what to expect in connecting and following the words in a sentence.
For punctuating sentences, commas have a couple of optional rules (as well as some "required" rules). One of those optional rules is, actually, not considered optional by many writers and editors. It's about using the serial, or Oxford, comma before a conjunction in a series of three or more items. The second sentence in my first paragraph above contains an example of not using it (after useful). But I'm not focusing on that comma here.
Instead, I'm focusing on the comma that may be used after introductory clauses and phrases in a sentence. The first sentence in the first paragraph begins with an example. So do the second and fourth sentences in the second paragraph. The first sentence in the third paragraph also begins with one.
Prompting this blog item is an article in the British newspaper The Guardian. It describes the actions of a 10-year-old student who challenged England's education secretary for inconsistent use of this comma in required school tests, called SATS (for statutory assessment tests).
For one of the tests, students had to insert a correctly spelled word missing from two sentences:
Question 6 read: "If there is not [blank] rainfall this month there will be a drought." Question 16 read: "As he was the [blank] of the tribe the final decision was his."The student protester, Rebecca Lee, contended that a comma is required after month in Q6 and tribe in Q16. She wrote:
I understand that you are very keen for us all to learn our complex sentences and use of accurate punctuation. I believe that your department should also use the correct punctuation in all the Sats tasks.But she added:
I would like to hear what you have to say about this and also whether you will perhaps admit that punctuation is often a matter of judgment, with not necessarily a single right answer.The article continues, quoting various authorities on this question. Rebecca's teacher at the Church of England primary academy in Clifton said:
The whole question with grammar is that it is flexible. But when you have to teach it for a test then you have to teach it as a rule.A spokesperson for the Standards and Testing Agency, an executive agency of the Department for Education:
The commas here are a matter of choice: they can be used to mark out clauses that appear at the beginning or the end of a sentence, but they are not necessary. We decided to use commas sometimes and not at others to make the tests more like real life where people will have their own styles.David Marsh, editor of the Guardian style guide:
You don't need to insert a comma between clauses, but doing so can make the sentence easier to read ....
Both examples are perfectly grammatical with or without the comma but I would be inclined to use a comma after "tribe" in the second one.
Reading such sentences out loud is a good guide. I pause slightly after "tribe", which suggests that a comma should be inserted. It adds a slight emphasis to the clause that follows. ...I like Marsh's suggestion about inserting this comma--to prompt a pause in reading. It can aid the reader by clarifying the relationship between the words before the comma and the words after the comma.
And, getting back to etiquette, inserting that comma is like pausing after introducing two people. It gives them a moment to remember the name or face or other identifying trait of the person they just met
Despite Marsh's advice for using the comma, he adds that it shouldn't be required. I agree that the comma may not be needed if the introductory clause or phrase is short, but I would emphasize that using it is never wrong.
Here's my related advice in the comma entry of Garbl's Editorial Style and Usage Manual:
[U]se a comma to separate an introductory phrase or clause from the rest of the sentence: After graduating from college, he joined AmeriCorps. It may be omitted after short introductory phrases (less than three words) if no ambiguity would result: On Thursday the Kennewick City Council will decide the issue. When in doubt, use the comma, especially when it separates two capitalized words.Also, FYI, here's my advice on using the serial comma (I'll add here that using it also is never wrong, unless your boss, professor or editor has a different expectation):
[I]n a series of three or more terms with a single conjunction, use a comma after each term: She opened the closet, grabbed a coat, and picked up an umbrella. In a complex series of phrases, the serial comma before the final conjunction aids readability. In a simple series, the comma is optional before the conjunction: The van is economical, roomy and dependable. Also, put a comma before the final conjunction in a series if an integral element of the series needs a conjunction: He likes folk, rock, and rhythm and blues. Don't put a comma before the first item in a series or after the and in a series.____________