ICT in Education Main Headline

Everything you need to know about hyphens (-), en dashes (–) and em dashes (—)

中文摘要 / Summary in Chinese

Sometimes it is longer, other times it is really short. You might have been confused by the small lines between words—like these—because all of them look similar but can vary in length and function.

Writers using the English language put a small line between words to denote some sort of relationship, and there are three of them: the hyphen, the en dash, and the em dash.

The hyphen is the shortest among the three, linking individual words together to form a compound lexical unit. The words being linked usually have a history of collocation. For example, when we think of the verb “provoke”, the word “thoughts” may come to mind. Hence, people use the compound adjective “thought-provoking” as a modifier of a noun. In other cases, fixed phrases such as “on the go” (meaning something keeps running), can be hyphenated to become a compound adjective, such as an “on-the-go charger”.

Hyphenated words are not only used as adjectives: modern English also allows quite flexible use of affixes in forming nouns and the like. “Pan-democrats” and “pro-communist” are some of the creative examples of this approach. Proper nouns can also be joined to indicate co-existence or cooperation between names, such as the very well-known “Hong Kong-Zhuhai-Macao Bridge”.

Technically speaking, the hyphen symbol is identical to the minus sign used in arithmetic when it comes to digital documents.

Next on the list is the en dash, which indicates a range. It has a similar meaning to the preposition “to” or “through”. Examples include “pages 4–9”, “Mon–Fri”, “14:30–16:30” and “24 July–1 August”. As you probably notice, an en dash is longer than a hyphen. It has been stated anecdotally that an en dash is exactly the length, typographically, of the letter “n”, thus giving it the name. On a Windows-based computer, an en dash can be rendered by the following key sequence: Alt 0150.

The em dash, on the other hand, is not as simple. Its function is different from the word-level linkage achieved by using hyphens. Instead, an em dash suggests relationship either between clauses, phrases or ideas. It has a similar size typographically to the letter “m”, it is said. On a Windows-based computer, the proper way to render an em dash is the key sequence Alt 0151

An em dash can be used instead of a colon. For example: “She did everything this morning—washing the dishes, hanging the clothes and cooking breakfast for her kids”. It can also replace a pair of commas or brackets: “You should ask Professor Chan—the one who taught you marketing last semester—to write the reference letter for you”.

In rare cases, the em dash is used to hide the full form of a word, either because the word is offensive or it is confidential: “The serial burglar, J——, was arrested in a police operation last night”. Last but not least, you sometimes see em dashes used in fictional work to indicate interruption of speech. For instance, In The Great Gatsby, when the narrator Nick Carraway talks about where he used to live, his words are rendered: “I lived at West Egg, the—well, the less fashionable of the two”.

To recap, hyphens are used in compound words, en dashes in describing ranges, and em dashes in phrases or clauses. If you still find hyphens and dashes confusing, bear in mind one simple rule: the longer the text items being linked, the longer the line you will need.

Name Symbol Key sequence on Windows computer* Shortcut in Microsoft Word on Windows computer* General shortcut on Mac computer HTML Code
Hyphen / Minus Same as the minus key
En Dash Alt 0150 Ctrl – Option – –
Em Dash Alt 0151 Ctrl Alt – Shift Option – —

* The digits 0–9 after the Alt key must come from a numeric keypad. Likewise, the minus sign after the Ctrl or Ctrl Alt combination must also come from a keypad.

By IFTM faculty members Mr. Wilson Hong and Dr. Simon Lei