Most readability formulas use the number of words in a sentence to measure its difficulty. Yet in some cases a short sentence can be harder to read than a long one. Comprehension can sometimes be facilitated by longer sentences, especially those that contain coordinate structures. (See Examples and Observations, below.)
- Sentence Variety
- Basic Sentence Structures in English
- Paragraph Length
- The Rhythm of Prose, by Robert Ray Lorant
- Sentence Variety in Alice Walker's "Am I Blue?"
- Sentence Variety in Thurber's "Life and Hard Times"
- What Is Sentence Combining and How Does It Work?
Examples and Observations:
- "When the great orator William Jennings Bryan accepted the Democratic nomination for president in 1896, the average length of a sentence in his speech was 104 words. Today, the average length of a sentence in a political speech is less than 20 words. We're simply in an age of directness and making our point more quickly."
(Bob Elliot and Kevin Carroll, Make Your Point! AuthorHouse, 2005)
- "Varying your sentence length is much more important than varying your sentence pattern if you want to produce clear, interesting, readable prose."
(Gary A. Olson, James DeGeorge, and Richard Ray, Style and Readability in Business Writing: A Sentence-Combining Approach. Random House, 1985)
- Examples of Varied Sentence Length: Updike, Bryson, and Wodehouse
"That laugh said a strange thing. It said, This is fun. Baseball is meant to be fun, and not all the solemn money men in fur-collared greatcoats, not all the scruffy media cameramen and sour-faced reporters that crowd around the dugouts can quite smother the exhilarating spaciousness and grace of this impudently relaxed sport, a game of innumerable potential redemptions and curious disappointments. This is fun."
(John Updike, "The First Kiss." Hugging the Shore: Essays and Criticism. Knopf, 1983)
"One of the great myths of life is that childhood passes quickly. In fact, because time moves more slowly in Kid World--five times more slowly in a classroom on a hot afternoon, eight times more slowly on any car journey of more than five miles (rising to eighty-six times more slowly when driving across Nebraska or Pennsylvania lengthwise), and so slowly during the last week before birthdays, Christmases, and summer vacations as to be functionally immeasurable--it goes on for decades when measured in adult terms. It is adult life that is over in a twinkling."
(Bill Bryson, The Life and Times of the Thunderbolt Kid. Broadway Books, 2006)
"The young man's judgment was one at which few people with an eye for beauty would have cavilled. When the great revolution against London's ugliness really starts and yelling hordes of artists and architects, maddened beyond endurance, finally take the law into their own hands and rage through the city burning and destroying, Wallingford Street, West Kensington, will surely not escape the torch. Long since it must have been marked down for destruction. For, though it possesses certain merits of a low practical kind, being inexpensive in the matter of rents and handy for the buses and the Underground, it is a peculiarly beastly little street. Situated in the middle of one of those districts where London breaks out into a sort of eczema of red brick, it consists of two parallel rows of semi-detached villas all exactly alike, each guarded by a ragged evergreen hedge, each with coloured glass of an extremely regrettable nature let into the panels of the front door; and sensitive young impressionists from the artists' colony up Holland Park way may sometimes be seen stumbling through it with hands over their eyes, muttering between clenched teeth 'How long? How long?'"
(P.G. Wodehouse, Leave It to Psmith, 1923)
- Ursula Le Guin on Short and Long Sentences
"Teachers trying to get school kids to write clearly, and journalists with their weird rules of writing, have filled a lot of heads with the notion that the only good sentence is a short sentence.
"This is true for convicted criminals.
"Very short sentences, isolated or in a series, are terrifically effective in the right place. Prose consisting entirely of short, syntactically simple sentences is monotonous, choppy, a blunt instrument. If short-sentence prose goes on very long, whatever its content, the thump-thump beat gives it a false simplicity that soon just sounds dumb. See Spot. See Jane. See Spot bite Jane. . . .
"As Strunk and White say, variety in sentence length is what's needed. All short will sound stupid. All long will sound stuffy.
"In revision you can consciously check for variety, and if you've fallen into a thumping of all short sentences or a wambling of all long ones, change them to achieve a varied rhythm and pace."
(Ursula Le Guin, Steering the Craft: Exercises and Discussions on Story Writing for the Lone Navigator or the Mutinous Crew. Eighth Mountain Press, 1998)
- "Don't Just Write Words. Write Music."
"This sentence has five words. Here are five more words. Five-word sentences are fine. But several together become monotonous. Listen to what is happening. The writing is getting boring. The sound of it drones. It's like a stuck record. The ear demands some variety. Now listen. I vary the sentence length, and I create music. Music. The writing sings. It has a pleasant rhythm, a lilt, a harmony. I use short sentences. And I use sentences of medium length. And sometimes, when I am certain the reader is rested, I will engage him with a sentence of considerable length, a sentence that burns with energy and builds with all the impetus of a crescendo, the roll of the drums, the crash of the cymbals--sounds that say listen to this, it is important.
"So write with a combination of short, medium, and long sentences. Create a sound that pleases the reader's ear. Don't just write words. Write music."
(Gary Provost, 100 Ways to Improve Your Writing. Mentor, 1985)
- Sentence Length in Technical Writing
"Sometimes sentence length affects the quality of the writing. In general, an average of 15 to 20 words is effective for most technical communication. A series of 10-word sentences would be choppy. A series of 35-word sentences would probably be too demanding. And a succession of sentences of approximately the same length would be monotonous.
"In revising a draft, use your software to compute the average sentence length of a representative passage."
(Mike Markel, Technical Communication, 9th ed. Bedford/St Martin's, 2010)
- Sentence Length in Legal Writing
"Keep your average sentence length to about 20 words. The length of your sentences will determine the readability of your writing as much as any other quality. That's why readability formulas rely so heavily on sentence length.
"Not only do you want a short average; you also need variety. That is, you should have some 35-word sentences and some 3-word sentences, as well as many in between. But monitor your average, and work hard to keep it to about 20 words."
(Bryan A. Garner, Legal Writing in Plain English. Univ. of Chicago Press, 2001)
- Sentence Length and Polysyndeton
"To dwell in a city which, much as you grumble at it, is after all very fairly a modern city; with crowds and shops and theatres and cafes and balls and receptions and dinner-parties, and all the modern confusion of social pleasures and pains; to have at your door the good and evil of it all; and yet to be able in half an hour to gallop away and leave it a hundred miles, a hundred years, behind, and to look at the tufted broom glowing on a lonely tower-top in the still blue air, and the pale pink asphodels trembling none the less for the stillness, and the shaggy-legged shepherds leaning on their sticks in motionless brotherhood with the heaps of ruin, and the scrambling goats and staggering little kids treading out wild desert smells from the top of hollow-sounding mounds; and then to come back through one of the great gates and a couple of hours later find yourself in the "world," dressed, introduced, entertained, inquiring, talking about Middlemarch to a young English lady or listening to Neapolitan songs from a gentleman in a very low-cut shirt--all this is to lead in a manner a double life and to gather from the hurrying hours more impressions than a mind of modest capacity quite knows how to dispose of."
(Henry James, Italian Hours, 1909)