Wikipedia's Manual of Style is one of our most important resources for shaping articles into a cohesive resource that people around the world can rely on. One reason Wikipedia is such a popular site is that it packages high-quality, reliable information in somewhat standardised style and format. The Manual of Style (or "MoS"—often pronounced "moss") aims to assist editors in this goal by providing a balance between two extremes:
a framework that is too strict for the variety of texts we offer, the writing preferences of individual editors, and their creative impulses; and
a framework that is too loose to provide the standardisation that makes us a cohesive authority on the Internet.
Please keep in mind that seemingly trivial aspects of English style can be important in giving our visitors a smooth reading experience. We hope that these exercises will help you to absorb and apply the MoS guidelines. Feedback is welcome on the talk page.
Hyphens and dashes are basic to stylish writing in English. Even if your readers aren't quite sure of the precise rules that govern their use, their reading will be easier and their comprehension aided by your knowing how to use them properly. The Manual of Style clearly sets out how to use all three punctuation symbols: hyphens (-), en dashes (–) and em dashes (—). If these three symbols are hard to distinguish (- – —), you may need to change your font or browser to a standard one that renders them properly.
If you're unsure how to input en dashes and em dashes, please see this.
Here, we present texts in which hyphens and/or dashes may be either wrongly used or wrongly absent; in other words, some of the examples are wrong, and some are right. Remember, mostly it's a matter of:
whether to use a symbol at all;
if so, whether to use a hyphen or en dash; and in a few cases
whether the symbol should be spaced or unspaced.
Em dashes are a quite separate beast, and much easier to use. Many writers don't use them at all; they choose instead to use spaced en dashes – like this – intead of unspaced em dashes—like this—for their "interrupters". It's up to you.
For each exercise, decide on the answer in your mind before clicking on the solution. In most exercises there's an intermediate hint.
Exercise 1.1
THE EXAMPLE:
Lady Featherstone-Morley carelessly ashed her cigarette on the butanol sample.
HINT:
Lady Featherstone-Morley carelessly ashed her cigarette on the butanol sample.
Does the hyphen indicate conjunction (joining together) or disjunction (the separateness of both elements)?
THE ANSWER:
The hyphen as given is correct. "Featherstone" and "Morley" are joined together here into a compound surname. Removing the hyphen would be wrong:
Lady Featherstone Morley
So would an en dash: there's no opposition or particular relationship between the names here, other than their coming together into someone's compound name:
Lady Featherstone–Morley
An em dash would look really gawky:
Lady Featherstone—Morley
Exercise 1.2
THE EXAMPLE:
During the period 2005-07, the number of articles on the English Wikipedia quadrupled.
HINT:
During the period 2005-07, the number of articles on the English Wikipedia quadrupled.
THE ANSWER:
The hyphen is incorrect. Here, there's a year range, requiring an en dash, which stands for "to":
During the period 2005–07,...
If the reader is already familiar with what you're saying, you might even drop "the period".
Many people prefer just two closing digits, as here, to the full expression ("2005–2007"). MOSNUM says that one and three closing digits are unacceptable.
Exercise 1.3
THE EXAMPLE:
From 2005–07, house prices in Capetown rose by a third.
HINT:
From 2005–07, house prices in Capetown rose by a third.
There's something inconsistent in the coloured text. Say it aloud.
THE ANSWER:
The example is incorrect; this is what you need:
From 2005 to 2007, house prices in Capetown rose by a third.
The en dash stands for "to", and that's how you'll vocalise it in reading it aloud. We need both prepositions spelled out: "from ... to", not "from ... –", which is awkward.
Either that, or recast it:
In the period 2005–07..., or During 2005–07 ...
Exercise 1.4
THE EXAMPLE:
The case was upheld by the Supreme Court in a 4–3 judgement.
HINT:
The case was upheld by the Supreme Court in a 4–3 judgement.
What word could be substituted for the symbol?
THE ANSWER:
The en dash is correct. An en dash can stand for "to", "against" or "versus"—these functions are all disjunct (indeed, adversarial) relationships between the items. It's the same for sports scores:
"The Vancouver Canucks massacred the New York Islanders in an 11–2 victory."
Exercise 1.5
THE EXAMPLE:
At -25°C, it was unseasonably warm in Yellowknife.
HINT:
There are two things wrong.
THE ANSWER:
At −25 °C, it was unseasonably warm in Yellowknife.
First, you may think this is an en dash, but it's a minus sign, which mathematicians are fussy about. Until early 2008, MOS used to allow en dashes for negative signs (−3.5) and subtraction operators (4 − 1 = 3); not any more. A minus sign is very subtlely different from an en dash—something to do with lying lower on the line. Squint and ... you won't see it. Here they are: hyphen, minus sign, the en dash, and the em dash: - − – — . As a superior race, these mathematicians have the run of the place. Hmmmph.
Second, MOS insists on a space between all values (−25) and units (°C), with two minor exceptions (angular degrees and geographical coordinates); so it's −25 °C, not −25°C. There's no space between the minus sign and the value (never − 25)
Take a look at how you should key it in:
At −25 °C, it was unseasonably warm in Yellowknife.
Exercise 1.6
THE EXAMPLE:
The dream inspired the introduction of supernatural and horror–themed lyrics.
HINT:
Two things wrong: The dream inspired the introduction of supernatural and horror–themed lyrics.
THE ANSWER:
The dream inspired the introduction of supernatural- and horror-themed lyrics.
It's hard to imagine that the author meant "supernatural lyrics". More likely, "supernatural-themed and natural-themed" lyrics, both adjectives requiring a hyphen to link them to their coupled word, "theme". The "hanging" hyphen is useful for making this double compound expression neater. It's a rare case in which a hyphen is followed by a space. See MoS.
Exercise 1.7
THE EXAMPLE:
Five classes at St Alban's High–comprising more than 100 students–will compete against each other to win a prize for the best Wikipedia collaboration on an article on their chosen suburb of Seattle
HINT:
Five classes at St Alban's High–comprising more than 100 students–will compete against each other to win a prize for the best Wikipedia article on a chosen suburb of Seattle.
These en dashes are "interrupters", like very strong commas, that occur in pairs to mark of explanatory text.
THE ANSWER:
::Five classes at St Alban's High – comprising more than 100 students – will compete against each other to win a prize for the best Wikipedia article on a chosen suburb of Seattle.
En dashes, when used as interruptors, must be spaced. The alternative is unspaced em dashes:
Five classes at St Alban's High—comprising more than 100 students—will compete against each other to win a prize for the best Wikipedia article on a chosen suburb of Seattle.
Exercise 1.8
THE EXAMPLE:
The 10-kilometre (16-mi) distance between the centres has been a major impediment to economic development.
HINT:
*There's nothing wrong with the choice of units or the fact of the conversion per se.
THE ANSWER:
The example is incorrect. The 10-kilometre (16 mi) distance between the centres has been a major impediment to economic development.
Sure, both main unit and conversion are used as double adjectives, describing "distance". But the ISO rules, which WP agrees with in this case, are that a hyphen must be used to connect a value and a fully named unit ("30-kilogram weights"), but must not connect a value and an abbreviated unit ("30 kg weights). Fussy, isn't it.
Exercise 1.9
THE EXAMPLE:
Australia–New Zealand Free Trade Agreement
HINT:
*Yep, an en dash is required, since a relationship is indicated where "and" could be substituted. But it's all in the spacing.
THE ANSWER:
The example is incorrect. The Australia – New Zealand Free Trade Agreement.
If one or either of the items has an internal space (here, "New Zealand") the en dash needs to be spaced as well. This is particularly relevant for full date ranges: "August 3, 1979 – November 30, 1980", not "August 3, 1979–November 30, 1980", ouch.
Exercise 1.10
THE EXAMPLE:
The season was fully-subscribed months before the first game.
HINT:
No hint this time.
THE ANSWER:
The hyphen is incorrect:
The season was fully subscribed months before the first game.
Say after me: "No hyphen after "-ly".
Why? you might ask. Because an "-ly" word, as an adverb, always qualifies a verb (an action), so your readers will already be expecting it to be joined grammatically to the next word. It's not rocket science. This is one of the most common hyphen glitches on Wikipedia.
Exercise 1.11
THE EXAMPLE:
In 2003, the name of the body was changed from "the British–American Commission" to "the Anglo–American Commission".
HINT:
Only one is correct with an en dash. Now we really are being fussy.
THE ANSWER:
The second en dash is incorrect; thus, "In 2003, the name of the body was changed from "the British–American Commission" to "the Anglo-American Commission".
Trivium of the day: an en dash should be replaced by a hyphen between two items if at one item (or both) is just a word particle. "Anglo-" is merely a prefix, whereas "British" is a full word; an acronym or abbreviation in this context would count as a full word ("US–UK agreement").
Aside: Compound items indicating race or nationality involve simple conjunction, so a hyphen is preferred: "African-American engineering professor"; this contrasts with "African–American trade talks", in which the en dash suggests a relationship or movement or direction, rather than mere conjunction.
Exercise 1.12
THE EXAMPLE:
African-American engineering professor
leading Chinese American singer
HINT:
Remember the difference in function between hyphens, en dashes, and a simple space between the words?
THE ANSWER:
The hyphen in "African-American" is correct. Compound items indicating race or nationality involve simple conjunction, so a hyphen is preferred to an en dash; this contrasts with "African–American trade talks", in which the en dash suggests a relationship or movement or direction, rather than mere conjunction—remember Lady Featherstone-Morley with no eyebrows?.
The space between the items in "Chinese American" is incorrect; it's a compound word that is easier to read with the hyphen. Thus, like "African-American", "Chinese-American" is the solution.
