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If you ever sprinkle a sentence with too many commas, or miss a few, this guide will keep you from repeating your mistakes.
Step 1: Form a compound sentence
Link two independent clauses to form a compound sentence with a comma after the first clause followed by a conjunction and the second clause.
Conjunctions include "and," "but," "yet," "so," "for," "nor," and "or."
Step 2: Separate a series
Separate a series of three or more words, phrases, or clauses by inserting a comma after each item but the last. Do the same for a series of two or more adjectives that modify the same word.
Whether you put a comma after the last item depends on the writing style you're following.
Step 3: Separate introductory elements
Use a comma after an introductory clause, phrase, or word to set it off from the rest of the sentence. For example, "Bob didn't mean to do it, but he did it anyway."
Step 4: Set off nonessential items
Enclose nonessential phrases, clauses, or words in the middle of a sentence between a pair of commas. For example, "Moisture in the air, which is also referred to as humidity, makes people feel warmer." Use one comma to set off nonessential items at the beginning or the end of a sentence.
Remove the phrase, clause, or word from the sentence to see if it is nonessential. A nonessential item can be removed without changing the meaning of the sentence.
Step 5: Use commas with quotations
Shift between a direct quotation and the identifying tag, or attribution, such as "she said," using a comma.
Step 6: Set off addresses, dates, and titles
Set off all geographical names, addresses, dates, and titles or degrees following a name with a comma.
Step 7: Prevent ambiguity
Prevent ambiguity in sentences that can be confusing by using a comma to indicate a pause to readers.
Did You Know?
Invented in 1448 by Johann Gutenberg, the printing press helped standardize the placement of punctuation.