Unit 21.6 - The Comma

· Use commas between the main clauses in a compound sentence.

· You may omit the comma between very short main clauses that are connected by a coordinating conjunction unless the comma is needed to avoid confusion.

· Use commas to separate three or more words, phrases, or clauses in a series.

· Place a comma between coordinate adjectives that precede a noun.

Coordinate adjectives modify a noun equally. To determine whether adjectives are coordinate, try to reverse their order or put the word and between them.

· Do not use a comma between adjectives preceding a noun if they sound unnatural with their order reversed or with and between them. In general, adjectives that describe size, shape, age, and material do not need commas between them.

· Commas may be needed between some of the adjectives in a series but not between others.

                e.g. I like to read in our bright, cozy family room.

1. Participles (verb that can function as an adjective), infinitives, and their phrases

Use commas to set off participles, infinitives, and their phrases if they are not essential to the meaning of the sentence.

2. Adjective clauses

          Use commas to set off a nonessential adjective clause (extra info).

3. Appositives

• Use commas to set off an appositive if it is not essential to the meaning of a sentence.
• A nonessential (nonrestrictive) appositive can be considered an extra appositive; it calls for commas.
• A nonessential (nonrestrictive) appositive is sometimes placed before the noun or pronoun to which it refers.
• An essential (restrictive) appositive gives necessary information about a noun and is not set off.

(5) Commas with Interjections, Parenthetical Expressions, and Conjunctive Adverbs

· Use commas to set off interjections (such as oh and well), parenthetical expressions (such as on the contrary, on the other hand, in fact, by the way, to be exact, and after all), and conjunctive adverbs (such as however, moreover, and consequently).

 

1. Prepositional phrases

· Use a comma after a short introductory prepositional phrase only if the sentence would be misread without the comma.

· Use a comma after a long prepositional phrase or after the final phrase in a succession of phrases.

2. Participles and participle phrases

· Use commas to set off introductory participles and participial phrases.

· Use commas to set off all introductory adverb clauses.

· Use commas to set off internal adverb clauses that interrupt the flow of a sentence.

· Use commas to set off an antithetical phrase.

(An antithetical phrase uses a word such as not or unlike to qualify what precedes it.)

1. Titles of people

2. Addresses, geographical terms, and dates

3. References

Use commas to set off the parts of a reference that direct readers to the exact source.

Use a comma to set off words or names used in direct address.

Use commas to set of a tag question.

Place a comma after the salutation of an informal letter and after the closing of all letters.

Misuse of Commas

• In general, do not use a comma before a conjunction that connects a compound predicate composed of only two verb phrases.
• Do not use only a comma to join two main clauses that are not part of a series. A sentence with this error is called a run-on sentence.
• Do not use a comma between a subject and its verb or between a verb and its complement.