1. Items in a Series
A series may consist of nouns, verbs, clauses, phrases, or sentences.
Comma is always placed before coordinating conjunction in technical writing.
Ex 1: The coach recommended dribbling, shooting, and passing.
Nouns in a series
Ex 2: I must ensure that my room is clean, that my brother is home, and that the garbage has been emptied
Clauses in a series
Textual Clues: 3+ items; comma Coordinating Conjunction

2. Two or More Adjectives
Adjectives are separated by commas when two adjectives modify the same word and do not modify each other.
EX 1: Lucia is an intelligent, thoughtful student.
Ex 2: I finally found a decent, affordable car.
Textual Clues: comma between adjectives can be replaced with and.

3. Independent Clauses
Separated by a comma when followed by one of the seven coordinating conjunctions.
EX 1: Amy followed the recipe carefully, for she had never made paella before.
EX 2: He was enraged, yet he was also jocular.
Textual Clues: Two independent clauses and coordinating conjunction.

4. Non-Essential Clauses
A clause is nonessential when it can be omitted from the sentences without changing the meaning of the sentence.
EX 1: Annie, who was a vegetarian, was killed by a rhinoceros, an herbivore .
EX 2: Ned, waiting for a train, got hit by lightening.
Textual Clues: participle or relative pronoun.

5. Introductory Elements
Precede the subject of the sentence.
Prepositional:
By the way, I will have gender reassignment surgery next week.
Adverbial:
When you are as old as I am, you will know that you can tune a piano but you can’t tune a fish.
Participial: During the long ride home, I finished all my calculus.

6. Introductory Elements
Textual Clues:
First word is either a preposition, an adverbial conjunction, or a participle.
Comma is placed directly in front of subject.

7. Interrupters Usually quite short and really do interrupt the sentence.
Ex 1: You know, Carl, you forgot to buy a whole chicken.
EX 2: Have you read Fup, a short novel about a family that owns a 20 pound mallard?
Textual Clues: These are frequently short, and they do not use relative pronouns. These can also be omitted from sentence without changing meaning.

8. Conventional Uses Dates: Addresses: October 1, 2009
October 1, 2009, is not my birthday.
Addresses:
Grayling, MI
Grayling, MI, is my home town.
1135 Old US 27 N, Grayling, MI, is the high school’s address.

9. Conventional Uses When a title follows a name.
John Doe, Ph.D.
Jane Doe, Ph.D., is a close friend who is dead, and whom I have never known.
Addressing a letter and signing off.
Dear John,
Sincerely, Jane