What comma rules did you learn at school?

Most of my teachers say something along the lines of 'use a comma when you need to take a breath'.

This rule sometimes works, but too often writers are either hyperventilating when they write, or hardly breathing at all. The effect on the reader, who tends to read internally so breathing isn't an issue, is just confusing.

So use commas to add meaning, not breaths, to your sentences. This comma usage might relate to a natural pause if you were reading aloud, but not necessarily.

The four comma rules below cover the occasions you are most likely to need commas in your everyday writing. If you keep your sentences short (I recommend 15-20 words on average), you won't need to worry about learning more.

Comma Rule # 1: Use commas to separate three or more items in a list.

For example:

Jayne went to the supermarket, the bookshop and the bank during her lunch break.

The comma separates the supermarket and the bookshop. You could have written 'the supermarket and the bookshop and the bank', but that doesn't sound right. So, in the example above, the comma replaces the first 'and'.

You can also consider using a bulleted or numbered list for this example.

Comma Rule # 2: Use a comma to separate two sentences that are stuck together with a joining word (and, but, or, so, yet, for).

There are simple sentences, and there are complex ones. Simple sentences don't need commas. Take these two:

I have seen the film. I didn't enjoy it.

You can join these two simple sentences together with a joining word like 'but'. This results in what is known as a compound sentence. If you do this, put a comma before the 'but', like this:

I have seen the film, but I didn't enjoy it.

The same rule applies when you join two or more sentences with the words 'and', 'or', 'so', 'yet' and 'for'. For example:

You can read the book, or watch the video if you prefer.

He wanted to talk to Lucy, so he called her at the office.

The safe was supposed to be secure, yet the robbers still managed to break it open.

John had to listen carefully, for the director spoke with a strong accent.

I have seen the film, and I really enjoyed it.

"Hang on a minute!" I hear you cry.

"At school we were told never to put a comma before 'and'!"

I had the same reaction when I first learned about this comma usage rule, so I checked it, several times.Trust me – it is correct to put a comma before the 'and' if you are sticking two or more sentences together.

Note that it is incorrect to join two sentences without a joining word, for example I have seen the film, I really enjoyed it. This is a very common mistake known as the comma splice

Comma Rule # 3: Use a comma in a complex sentence beginning with words like when, as, since, if, although, so, because, until and for.

This is similar to tip # 2, in that it deals with complex sentences, but with a twist.

Look at this example:

When we receive your payment, we will send you the goods.

There are two parts to this sentence – the part before the comma and the part after it. It's a complex sentence. The part after after the comma can stand on its own as a simple sentence:

We will send you the goods.

This is known as the main clause of the sentence. But the part before the comma can't stand on its own, as it is not a complete sentence in its own right:

When we receive your payment...

This is extra information relating to the main clause. When you start a sentence with the words above, separate the extra information from the main clause with a comma. This makes it easier to read. If you don't believe me, try reading the second sentence of this paragraph without the comma.

However, you don't need a comma if your main clause is at the start of the sentence. For example:

We will send you the goods when we receive your payment.

Confused? Don't worry. It gets easier with practice. If you really struggle with this comma rule, just avoid starting sentences with 'when', 'if', 'because', 'although' and so on.

Comma Rule # 4: Use a pair of commas when you are inserting extra information in the middle of a sentence.

Take this sentence:

Mr Smith will contact you next week.

It's a simple sentence, but who is Mr Smith? Perhaps I should add some extra information to make it clearer.

Mr Smith, our sales manager, will contact you next week.

In this version I've inserted the extra information into the sentence, and surrounded it with commas. In this case, I am using the commas in the same way as a pair of brackets. This is also correct, but there's a danger your writing will soon be covered with brackets, which makes it harder to read. See the section on brackets for appropriate usage.

The most common mistake people make in this situation is only using one comma. You wouldn't use just one bracket, would you? Well, it's the same for comma usage tip # 4.

How do you know you've put them in the right place? Easy. If you take out the words between the two commas, the sentence still makes sense. Take this example:

The woman I spoke to, Alice Wright, said I would receive the information by the end of the week.

If we take out the words between the pair of commas, we are left with:

The woman I spoke to said I would receive the information by the end of the week.

For the use of the comma in setting off direct speech, see the page on quotation marks.

And there you have it. All you need to start breathing and using commas correctly. Comma rules don't have to be any more complex than that!