Commas

A comma is a punctuation mark (,) used to indicate a pause between parts of a sentence or to separate items in a list.

You should use a comma before a conjunction (like 'and', 'but', 'or') when it connects two independent clauses.

An independent clause is a group of words that can stand alone as a sentence because it has a subject and a verb.

A dependent clause is a group of words that cannot stand alone as a sentence and usually begins with a subordinating conjunction (like 'because', 'although').

Use commas to separate items in a list. For example: 'I bought apples, oranges, and bananas.'

A non-essential clause adds extra information to a sentence but can be removed without changing the sentence's meaning. It is set off by commas.

My brother, who lives in New York, is visiting us.

Use commas to separate two or more adjectives that equally describe a noun. For example: 'It was a long, tiring day.'

Do not use a comma when the adjectives are not equal or when they are part of a single idea, such as 'a big red balloon'.

A compound sentence is a sentence that has at least two independent clauses joined by a conjunction.