Punctuation Department · Today with The Mayor

Comma

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Comma

The Mayor teaches this column himself. Work through each capitalization job below, then take the quiz.

Separate the items in a series

A comma separates each item in a series of three or more, including the serial (Oxford) comma before the final and or or. The serial comma prevents a list from reading as if the last two items were one.

In a sentence

The museum has paintings , old coins , and a real mummy.

Now you try

Three or more items in a row, each split by a comma, with one before the and. You could try snacks, school supplies, or pets.

Put the comma before the coordinating conjunction

A comma precedes the FANBOYS conjunction joining two independent clauses. A comma splice joins two independent clauses with only a comma. The clauses being related in meaning does not make the splice correct; it still needs a conjunction or a stronger mark.

In a sentence

The team practiced all week , yet they lost the final.

Now you try

Each side has to stand on its own. Like: I was tired, so I rested.

Set off the part you could lift out

A pair of commas sets off a nonrestrictive (nonessential) element, including a parenthetical expression that interrupts the sentence. The same job can be done with parentheses (Defense Attorney Parentheses) or a pair of dashes (Dash); the comma version is the quietest of the three.

In a sentence

My uncle , who fixes old cars , lives next door.

The plan , of course , worked perfectly.

Now you try

Drop in a who or which part: My bike, which is blue, is fast.

Set off the introduction before the main idea

A comma follows an introductory element (a word, a phrase, or a subordinate clause) before the main clause, so the reader sees where the introduction stops and the main clause begins.

In a sentence

Meanwhile , the rain kept falling.

Now you try

Start with Yes, First, or an After ... phrase: After lunch, we played.

Every comma does one job

Every comma job separates or sets off part of a sentence so meaning stays clear. A comma marks where a reader pauses, but the pause follows from the structure; the comma never joins two independent clauses on its own.

In a sentence

The bridge , which was built in 1930 , still stands.

It rained , so the game was moved.

Now you try

Series, join, set apart, or introductory. Every one of them separates.