By Mary Morel
Dashes are stronger than a comma and less formal than brackets. You use a longer dash to separate information and a shorter dash to link words.
Em and en rules are sometimes called em and en dashes.
The em rule (—)
The em rule is roughly the width of a capital M and is commonly known as a dash.
You use the em rule to separate text when you:
- mark an abrupt change in the direction of a sentence
The weather is wonderful—how was your holiday?
- provide additional or explanatory information
Make sure your passport is current—you have to pay a premium to get a passport in a hurry.
- isolate statements within a sentence
No-one—except the secretary—remembered to bring their lunch.
The Australian government style manual, Style manual: For Authors, Editors and Printers, recommends no spaces round the em rule.
Business writing style for a dash
In business writing, many writers use the Microsoft default for a dash (sometimes called a textual dash). It looks like an unspaced en rule.
The weather is wonderful – how was your holiday?
I used to use the traditional em rule, but have switched to the Microsoft default and like it.
The en rule (–)
The en rule is half the width of an em rule, or about the width of the letter e. It is a bit longer than a hyphen.
The en rule links text. You use the en rule to:
- link figures, time and distance
- show an association between two separate words
According to the Australian Government Style Manual, an en rule is unspaced if one word or figure is linked, but spaced if there is more than one linked word on either or both sides.
Sydney–Melbourne flights, but 45 BC – 1600 AD.
Business writing use of hyphens and en rules
In business writing, many writers use a hyphen instead of an en rule, but an en rule is useful because it creates more space between items.
Online grammar programs
Learn more about punctuation with my online course, An A to Z of Punctuation ($A39)