I can give you a little condensed version...however, if you want to attend a class, I won't be teaching again for another 4 years (when the little one goes kindergarten).
I'm guessing most of you don't get through #2(this is some dry reading!)
The biggest job a comma has is to seperate a sentence into managable elements.
1. Use commas after introductory phrases or clauses. "While I was smoking a cigar, my wife hollered at me to take out the trash."
A common mistake here is when you put a comma after the main clause and seperate the dependant clause:
"The mailman knocked on the door, while I was taking a dump." (Wrong.)
If you switched the sentence around, the comma would be necessary...
"While I was taking a dump, the mailman knocked on the door." (Right)
2. Use commas to highlight a word or phrase that isn't essential to a sentence. You're basically placing a pause before and after the word. (In this case, if it is a longer phrase, you can use a dash before and after the phrase.)
Some questions to ask whether the clause is essential:
a. If you leave out the clause, phrase, or word, does the sentence still make sense?
b. Does the clause, phrase, or word interrupt the flow of words in the original sentence?
c. If you move the element to a different position in the sentence, does the sentence still make sense?
"You're pretty good at identifying cigars. In this case, however, you're all fucked up."
3. Don't use commas to set off essential elements in a sentence.
"The lighter, that i borrowed from you, is out of butane." In this case, the commas should NOT be there because the clause "that I borrowed from you" is essential to identify which lighter. These clauses are directly following a noun and are acting adjectivally. They can also follow a verb, "He believes that the Acid Kuba Kuba is the best cigar ever." In this case the clause is acting adverbially.
Okay, my fingers are getting tired of typing so here are some more with examples.....
4. Use commas to set off 3 or more words in a series.
"I love Fuente, Padron, and Ashton cigars."
5. Use commas to seperate coordinate adjectives. Coordinate adjectives have equal status in describing the noun
"He was a stupid, pretentious idiot." (Make sure never to put in a comma after the second adjective.)
6. Use a comma near the end of a sentence to separate opposing coordinating elements.
"He was just ignorant, not stupid."
7. Use commas between the main text and a quotation.
CC wrote, "List them for us."
8. Most importantly, use commas to seperate independant clauses when they are joined by the coordinating junctions-
and
but
for
so
or
nor
yet
"Heftysmokes knows grammar, but Coventrycat called him out."
There is more I'm forgetting and I could go way in depth, but I haven't picked up a book since my boy was born!
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