Introduction

If your punctuation is unclear, it’s harder for your tutor to make sense of your work and you are likely to lose marks as a consequence. Good clear writing is also essential for virtually all graduate jobs. Poor comma use can make your writing unclear and very hard to follow. This guide explains the basics of getting comma use right.

Main uses of the comma

Forget what you learnt about a comma indicating a pause in a sentence: a comma has 3 specific functions.

1. Listing

The comma replaces and and or in a list.

For example:

• Good academic writing is uncluttered , uses direct , unambiguous language and always has a central thesis.

You must always write and or or before the final point in the list. Most people do not put a comma before and (we haven’t throughout this guide) but it is grammatically correct to do so. Formally, this type of comma is known as the Oxford comma).

2. Bracketing

This is the most common, and most complex, use of the comma. The comma functions in the same way as a bracket ( ) and indicates to the reader that you are providing a non-essential, but interesting, point.

For example:

• The bracketing comma is the most frequently used and , unfortunately, the most frequently misused comma.

This form of comma can also appear at the start or the end of a sentence, although in this instance only one comma is needed.

For example:

• Unfortunately, the bracketing comma is the most frequently used and the most frequently misused comma.

It would be incorrect to write

• ,Unfortunately, the bracketing comma is the most frequently used and the most frequently misused comma.

3. Joining

A comma can join two complete sentences together and must be followed by and, or, but, nor, while, for, yet.

For example

• Correctly coding the programme was time-consuming , but doing so was essential to gaining good marks.

This is very similar to the main use for the semicolon.

Summary

The comma has three main functions:

• To define a list
• To indicate a non-essential, but interesting, piece of information
• To join together two complete sentences

Common mistakes

Apart from not following the rules above, the most common mistakes students make is to write very long sentences and pepper them with commas. In most cases, it’s better to write shorter sentences, typically 15 – 20 words long. (Advice from the Plain English Campaign )

Further information

In most instances, the best way to learn punctuation and grammar is to read about it in a good textbook or website which contains practical exercises. Most tutors haven’t time to help individual studentswith grammar, but they may be able to recommend a good text to look at.