Commas

A sign shows the correct way to use a comma to avoid confusion or mixed messages.

Commas are used to separate words in a list and clauses in a sentence.

Here are some examples of commas in lists:

Her bag contained climbing shoes, rope, karabiners, chalk and a map.

He had walked through the mountains in Wales, Scotland, Norway, Turkey and Greece.

She loved dancing, paragliding, reading, yoga and singing.

Note that if you use a list of adjectives to describe something, the last one does not use a comma. For example:

He was a grumpy, old, small-minded man.

It was a blue-skied, beautiful, wide-open day.

In a complex sentence, use commas to separate the main and subordinate clauses.

For example:

  • Jones runs the bakery, which is on Main Street.
  • Sam Haskins, who broke his leg in a car accident, still managed to pass all his exams.

Sentence separation and comma splicing

A common mistake in writing is to place a comma where in fact a full stop is needed. This misuse of the comma creates what is called a 'comma splice'. Aim to avoid comma splices in your writing.

Proofread your work carefully and make sure you have put a full stop instead of a comma at the end of each sentence.

For example:

The room filled with smoke, I froze in panic.

This is an example of a comma splice. The comma in the middle should not be there because each half is a complete sentence in its own right.

So in fact the writer should have used two full sentences, each ending with a full stop. This would make for two short, lively sentences.

The room filled with smoke. I froze in panic.

Alternatively - a connective could connect these two sentences:

The room filled with smoke and I froze in panic.

OR – as these two sentences are closely linked, a semi-colon would also work:

The room filled with smoke; I froze in panic.

Question

Identify the comma splices in the following piece of writing. As you find each comma, think about what would happen if it were replaced with a full stop. Remember that the two sentences each side of a full stop must be meaningful and complete.

I hadn’t been to Mo’s house before, he lived at the end of the street, next to the playing fields. His front door was a faded blue, the paint peeled from the windowsills. The door was unlocked, or rather, couldn’t lock because where the lock should have been there was instead a hole. A piece of string hung limply from it and when we arrived Mo smiled shyly, he wasn’t embarrassed, I don’t think, this was, after all, his home.

Without comma splices:

I hadn’t been to Mo’s house before. He lived at the end of the street, next to the playing fields. His front door was a faded blue; the paint peeled from the windowsills. The door was unlocked, or rather, couldn’t lock because where the lock should have been there was instead a hole. A piece of string hung limply from it and when we arrived Mo smiled shyly. He wasn’t embarrassed, I don’t think. This was, after all, his home.