Many writers think it is a good idea to sprinkle commas every few places in there
writing, but this makes for difficult reading.

Here are some places commas should not be used:

* After and, but, and or, unless the comma sets off a dependent clause (a phrase
which can’t stand alone as a sentence).
Examples:
Wrong- But, she did get it done on time.
Right- But, to be fair, she did get it done on time.

* Between a month and year in a date: NOT November, 1990,
The comma stops two sets of numerals from running into one another. WRIGHT
November 20, 1990.

* Some style guides call for omitting the comma after very short dependent clauses
at the beginning of a sentence: NOT “On Saturday, the office is closed.” WRIGHT
“On Saturday the office is closed.” But do use a comma after long dependent causes:
“Because the entire epic is concerned with justifying the ways of God to man,
Milton must present free will in a positive light.”

* Commas are preferred before the last item in a list: leaving them out, as in “the
first, second and third chapters,” is a habit picked up from journalism. Though it
saves a little space and effort, omitting the final comma suggests the second and
third chapters are some sort of special pair.

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