What is a comma?

  • A comma helps to make meaning clear by separating words, phrases or clauses in a sentence.

  • Commas are used to separate clauses, coordinate adjectives and items in a list.

  • Commas are also used to introduce direct speech.

A professional drone instructor explains why commas are important to his work

For such a little punctuation mark, commas do a lot of work and have a number of different jobs. Here are some of the main ones:

Commas and lists

Commas are used to separate items in a list:

I play netball, basketball, hockey and football.

Commas and adjectives

Commas can also be used to separate coordinate adjectives. We can describe adjectives as coordinate when the order is not important. They can be rearranged in front of a noun:

She lifted the heavy, dusty book from the shelf.

Could also be written:

She lifted the dusty, heavy book from the shelf.

Commas and clauses

Commas are used to separate some types of clause in a sentence.

Subordinate clauses add extra detail to the main idea in a sentence and need a comma.

The team, preparing for their next game, were training outside.

Unhappy about his result, Jamie resolved to try harder next time.

Independent clauses that are joined by coordinating conjunctions - and, but, for, or, nor, so, yet - also need a comma before the conjunction.

Malik opened the door, and Helen was waiting inside.

Commas and direct speech

Commas are used to punctuate direct speech by 'introducing' the speech:

The director shouted, "Action!"

You also need a comma if the sentence continues after the speech:

The director shouted, "Action", and the actors began the scene.

Commas quiz

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Where next?

Discover more about this topic from around Bitesize.

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