103 Commas (English)

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Understanding Commas

Commas are the most widely utilized and under-appreciated form of punctuation in the English language. That means they are used the most and appreciated the least. More importantly, they are less understood than they should be. Understanding proper comma usage can be distilled into an art form when considering some of the finer points of the grammar rules regarding comma usage.
Proper comma use can save money in marketing expenses, prevent ambiguity that could have a legal or financial impact, and ensure transcripts are interpreted as intended. However, proper comma usage alone is meaningless unless there is proper understanding and interpretation of that usage.
As overlooked as commas may be in modern day, they still control the meaning of a sentence and the interpretation of that meaning. As such, it is imperative that the correct interpretation is derived with the proper understanding of smartly assigned commas in a sentence. That is to say, nothing can be more important than knowing and understanding proper comma usage grammar rules for healthy communications.

Commas and Independent Clauses

A comma can separate two independent clauses when the comma is followed by a conjunction (for example, but, and, or). We know that an independent clause is composed of a subject and a predicate. Two subjects, each with their own predicate, are separated by a comma if there is a conjunction present, such as and or but. If the comma is not followed by a conjunction, then a semicolon is used to separate the two independent clauses. In rare cases, a colon can be used to separate two independent clauses provided the first introduces the latter. In most cases, a comma and a conjunction are the most common separators of independent clauses aside from periods.
When one of the clauses is not independent, then that clause is referred to as a restrictive clause. All independent clauses are non-restrictive clauses. For example, Papoose is barking and is a dog, is an independent clause followed by the dependent clause, or restrictive clause, or less popularly restrictive parenthetic expression, of the declaration of Papoose's species. If a subject would be included in the latter half, clarifying that it is Papoose that is a dog, then a comma would be appropriate before the conjunction. To rephrase, there is only one subject followed by two predicates, so no comma is used.

Commas and Lists

Commas separate list items. These commas are referred to as series commas. The last comma in a list, typically preceding the conjunction, is referred to as a Series comma, Serial comma, or Oxford comma.
A comma is used to separate items in a list regardless of whether the list is provided inline or external, as is the case with a bulleted list. Commas can be omitted in external lists provided the items are not independent clauses, do not comprise a list of items with a common theme when grouped together aside from the introductory sentence that binds them, nor when other punctuation is used. List items may or may not include an Oxford comma (syn: serial comma, series comma) depending on the medium in which the sentence is being delivered.
For example, a list of beneficiaries in a will shall not exclude an Oxford comma because the conjunction without the serial comma could imply the last two beneficiaries in the list are grouped as one entity among the other listed members. On the contrary, a list of marketing slogans on a piece of collateral would spare the extra comma because it doesn't add value to proper interpretation of which items are included in the list. In advertising jargon, the common term for the act of not including the serial comma is known as 'sparing the ink' or, more familiarly, 'spare the ink.'

Hard Commas

Hard commas are used to separate items in a list that within themselves contain commas. Often, semicolons are deployed to act as hard commas, but replacing a hard comma with a semicolon is not a formal rule for lists containing items that themselves contain commas. For example, I have three red, green, and blue pens, four small, medium, and large erasers, and ten short, long, and extra-long highlighters. That same sentence can be written as: I have three red, green, and blue pens; four small, medium, and large erasers; and ten short, long, and extra-long highlighters. Either sentence can be said to be following proper rules; however, the example with semicolons as hard commas makes it easier to read the sentence and identify the breaking points in the main list.

Commas and Appositives

Commas separate appositives to set them off as parenthetic expressions when using closed-form style or when the appositive is more than a word or two long. For example, I Papoose might say, "I, Papoose the writer, am defining." The first appositive, Papoose, which follows I includes the use of open form, and the second appositive, Papoose the writer, includes the closed form style. Many recent literary materials show preference for open-form comma style, but only when adding the commas does not add or remove value to or from the rest of the sentence.

Commas and Parenthetics

Parenthetic clauses, or parenthetic expressions, are any non-restrictive clauses that can be easily removed from the sentence without changing its central meaning. That is to say, a parenthetic clause is separated on both sides by a comma if it can safely be removed and the meaning of the sentence stays the same. A parenthetic expression may add value to the paragraph or section in which it is included, but specifically within the sentence, it does not change the meaning of the main clause.
For example, the cat, a furry green ball of excitement, is ready to play with a mouse. In this example, the sentence can easily be reduced to: the cat is ready to play with a mouse, and the meaning stays the same. The parenthetic expression that can be removed in that example is also an appositive because it is directly modifying the noun that precedes it.

Commas and Numbers

A comma separates every hundredth numeral in a number. When you write one million in a sentence, the only commas are inside the number provided it is not the beginning or end of a parenthetic expression. For example, The 1,000,000 customers all bought the same style. Note: numbers greater than or including ten should be spelled out, regardless of usage. Numbers in date format are exceptions to this rule.

Commas and Memos

A comma is used when following the name of the recipient when addressing the recipient in a letter. A common exception is to use the colon after the recipient's name or title (or role), provided what follows is not an informal message nor personal or private in nature.
A comma is used when introducing your signature at the end of a letter, email, or impersonal note. A common exception is to remove the comma and insert a hyphen directly preceding the signature, whether if all on the same line or the hyphen and signature are broken onto the next line.

Commas and Quotes

A comma is used when introducing quoted words. This commonly known style is familiar in fiction stories that contain dialogue. Other uses include parenthetic expressions that are set off either by only two commas before and after and by single or double quotes, but commas are omitted when the parenthetic expression is set off by an en-dash, em-dash, hyphen, parentheses, brackets, curly braces or one of the styles of slashes.

Commas and Adverbs

Commas follow an adverb or adverbial phrase when followed by an independent clause. When the adverb is a single word and followed by a dependent clause, the comma is omitted. When a single-word adverb is placed between the words of a subject of an independent clause, then common style is to omit the commas surrounding the adverb per the open form rules established for appositives and parenthetic expressions, allowing for commas to be used if the sentence dictates a pause when being read.
In the rare cases when the adverb or adverbial phrase is in the predicate of an independent clause or in a dependent clause, it follows the rules of closed-form style for commas.
In some rare cases, such as when preceded by an independent clause that is separated by a semicolon, a comma is used regardless of what follows. This exception is a violation of the general rule of adverbial phrases or adverbs, but is still employed on rare occasions.

Commas and Double Words

Current best practices are to separate the occurrence of a double word with a comma. The most common example is, that that is, and that that isn't. Proper grammar usage per the currently accepted standards is to separate each occurrence of a double word with a comma; however, Papoose asks this one simple question: why not recast the sentence?
In the above text, Papoose provided an example where her will was tempted to double itself, but another synonym was found to replace the second occurrence of her will and avoid an unnecessary grammatical exception, because separating the double use of a word is not a task suitable for commas. Commas are intended for other purposes. The same word should not occur twice consecutively in any sentence under any circumstance. A seemingly unavoidable doubling of a word dictates the need for a thesaurus and defines the necessity of a style guide.