Use a Comma to:
Connect two independent clauses
with a coordinating conjunction: for, and, nor, but, or, yet, so.
- He wanted to watch his sister play soccer, but his girlfriend insisted on going to the movie instead.
Follow introductory words and phrases at the beginning of a sentence
Introductory words include moreover, therefore, thus, yes, no, well, please, however, still, yet, oh.
- However, when she got there she wasn’t hungry.
Introductory Phrases include:
An infinitive phrase:
- To get where he was going, Frank had to walk the long way around.
A prepositional phrase of more than four words:
- Through the walls of her bedroom, she could hear her parents quarreling.
Follow a dependent or subordinate clause that comes at the beginning of a sentence
- Because she scored very high on her SAT, Jennifer was admitted to five top-ranked schools.
Separate items in a list of words, phrases or clauses
when there are no commas within the listed items.
- He decided that he would write a resume, fill out a job application, and submit it to the pizza parlor before the end of the day.
Separate coordinate adjectives that describe the same noun
- She wore a green, flowing gown to the dance. (Both “green” and “flowing” modify the noun “gown.”)