HBR Guide to Better Business Writing - Bryan A. Garner 2013
A dozen punctuation rules you absolutely need to know
1. Hyphenate your phrasal adjectives.
A small-business incentive is different from a small business incentive. A limited-liability clause is different from a limited liability clause. When two or more words as a unit modify a noun, they must be hyphenated (unless certain exceptions apply). So a hotel’s door sign advising the staff not to disturb the guests would be a do-not-disturb sign. A company that is 25 years old is a 25-year-old company.
There are some exceptions: (1) Don’t hyphenate simple phrases formed by an -ly adverb and a past-participial adjective exaggerated claim>. (2) Don’t hyphenate phrases formed with proper nouns or foreign words . (3) Generally, don’t hyphenate phrasal adjectives used after the noun they modify , but there are exceptions based solely on conventions of usage .
2. Use a comma before and or or when listing three or more items.
Although simple series might not require the so-called serial comma before the conjunction to be perfectly clear, clarity fades fast as series become longer and more complex . So what is the rule?
The Chicago Manual of Style and other authorities on professional, technical, and scholarly writing almost universally endorse using the serial comma in all series for one good reason: It is sometimes wrong (ambiguous or worse) to omit it, but never wrong to include it.
3. Don’t use a comma to separate two compound predicates. Do use punctuation—usually a comma but a semicolon if needed for clarity—to separate a series of three or more compound predicates.
When two predicates share the same subject, it’s common not to repeat the subject. If the second clause repeats the subject, then the comma is proper before the conjunction . But if the subject isn’t repeated (is shared by both predicates), there should be no comma before the conjunction . When three or more such clauses are combined (sharing the same subject), the predicates become a series and do require at least a comma to separate them .
When one or more of the parts in the series contain commas, use semicolons instead to separate the predicates . The same principle holds for a compound predicate .
4. Don’t use an apostrophe to form plural nouns.
The use of apostrophes to form plurals (rather than possessives or contractions) is almost always incorrect. Most proper nouns take a simple -s, while those ending in -s, -x, -z, and sibilant -ch or -sh take -es. The exceptions to the no-apostrophe rule are for lowercase letters and capital letters when an apostrophe might prevent a miscue . Don’t use apostrophes to pluralize numbers or capitalized abbreviations without periods . The usual way to pluralize words and letters is to italicize the word or letter and append -s in roman type .
The incorrect use of apostrophes is especially common when pluralizing names. Mr. and Mrs. Smith are the Smiths, not *the Smith’s (or *the Smiths’). Mr. and Mrs. Stevens are the Stevenses (not *the Steven’s or *the Stevens’).
5. Don’t separate the grammatical subject from the verb, unless there’s a set-off intervening phrase.
As a rule, words and phrases that go together should be together, not unduly separated. So an appositive, for example, is next to the noun or pronoun it elaborates and a pronoun should not be so far from its antecedent as to make the connection unclear. On the same principle, the subject and verb in a sentence are best kept close together so that the sentence does not wander off on tangents.
That’s not to say that an intervening phrase or clause between the subject and verb is always wrong. It can be an effective way to modify the sense or add information . Although this technique adds emphasis to the modifying matter, it’s often clearer to make the phrase or clause introductory so that the subject and verb remain close .
6. Use bullets as attention-getting devices, but don’t overuse them.
Bullets draw the reader’s eye to a list of points without signaling that they’re presented in a certain order. The best lists follow these rules:
o Set up the list with an explanatory sentence in the form of an introduction that ends with a colon.
o Keep all the items parallel in grammatical form (all noun phrases, say, or all predicates starting with verbs) and somewhat similar in length.
o Present the items with a hanging indent so the bullets stand out to the left and all the lines of type align.
o Typeset the items single-spaced, perhaps with a bit of extra spacing between items.
o Keep the bullets simple in appearance, eschewing whimsical artwork in favor of solid bullet dots about the size of a lowercase o.
As with any other design device aimed at signaling emphasis or attracting the reader’s attention, the overuse of bulleted lists dilutes their impact.
7. Avoid quotation marks as a way of emphasizing words.
Quotation marks can send mixed signals. Most often they signal their traditional function: to set off a quotation. Sometimes they suggest a snide attitude , or perhaps imply that what they contain is not what it purports to be at all . They can be the equivalent of introducing the words with “so-called.” Given all these different possible meanings, quotation marks are a poor choice for emphasizing words and phrases. That is traditionally the role of italic type, an unambiguous signal.
Also avoid (1) underlining, the italic font’s uglier equivalent from the typewriter era; (2) overuse of boldface type, which is best reserved for titles and headings; and (3) all caps, which is irritating and hard to read if longer than a word or two.
8. Don’t hyphenate most prefixed terms.
American English is generally averse to hyphenating its prefixes (anteroom, biennial, deselect, proactive, quarterfinal, semisweet). Avoid the practice of inserting a hyphen, even when it results in a doubled letter (cooperate, reelect, misspeak). But there are a few exceptions: (1) when it’s needed to avoid a miscue or an ambiguity (re-create, re-lease, re-sign); (2) when the root word is a proper noun (pre-Halloween sales); and (3) when using certain prefixes such as all- (all-inclusive), ex- (ex-partner), and self- (self-correcting).
9. Use a colon or a comma—never a semicolon-after a salutation.
Colons are standard in business correspondence , commas in personal letters . Commas may also be permissible for business letters, depending on the personal relationship between the sender and the recipient. But to use a semicolon (*Dear Mr. Jones;) is always incorrect.
10. Long dashes have two defensible—and valuable— uses: to frame and to emphasize.
First, long dashes—called em-dashes—frame what is basically parenthetical matter and make it stand out. Notice in the first sentence how “called em-dashes” stands out. It could just as easily have been set off from the rest of the sentence by commas or placed inside parentheses. But the dashes give an interruptive phrase special emphasis (while parentheses almost beg to be skipped over). It’s a strong technique that should be used but, like all effective writing devices, not overused. Second, em-dashes are handy for short tags that sit apart from the main sentence. The em-dash replaces the colon but adds emphasis. The setoff can come at the beginning of the sentence or at the end .
11. Don’t use a comma when writing a month and year.
Stylebooks have long agreed that no comma should appear between the month and year . With the standard American format of month-day-year, do use a comma after the day . No comma is necessary with the day-month-year format <23 February 2012>. Use a comma after the year unless the date is used adjectivally .
12. For singular possessives, add S even if the word ends with an -s, -z, -x, or -ss.
This is the first rule in Strunk & White’s famous book The Elements of Style: A singular possessive takes ’s <theactress’s endorsement>. But note that personal pronouns and who have their own form without the ’s (mine, our, ours, your, yours, his, her, hers, its, their, theirs, whose). Also, if the name of a corporation or other entity is formed from a plural word, add only the apostrophe .</the
When forming a plural possessive, use the word’s standard plural form and add an apostrophe to the final -s . An exception applies to plural words that don’t end in -s: they follow the same rule as singular possessives .