Frequently asked questions about readability

Q. I've heard that short sentences communicate better than long ones. How long should an average sentence be?

A. Strive for sentences that are no longer than 17 words - 19-21 words if you're writing for a college-educated audience.

Q. Does that mean that every sentence should be about 17 words long?

A. No. Sentences that are essentially the same length destroy the rhythm of writing. You're seeking an average. That means you may have some sentences that are 25 or 30 word long and others that contain no more than four or five words. But I'd avoid sentences longer than 30 words.

Q. Isn't it possible to write long sentences that communicate well?

A. Yes. If the sentences flow well. For the most part, though, long sentences make it harder for the reader to grasp the message, because they contain too many ideas. The shorter the sentence, as a rule, the fewer the ideas. Tip: Consider the period your best friend, and use it often.

Q. Several writing formulas also counsel against long words. Would you explain why?

A. As a rule, the more prefixes and suffixes added to a word, the more abstract the word becomes. And abstract words don't communicate quickly. Take the word "serve," for example. You can "serve" people or "serve" in tennis, and so on. Now add the suffix "ice," and you've got "service," a slightly more complex word, but one that's still easy enough to understand. But if you add "able" to "service" and create "serviceable," the word becomes even more abstract. Now, let's go one step further and add the prefix "non" and you've got "nonserviceable," a much more complex word.

Q. Should we avoid long words altogether?

A. Of course not. But we should challenge every one we use to make sure the reader will easily grasp our meaning. And we should avoid using several long words in a row whenever possible.

Q. Aren't there several readability formulas based on the length of sentences and words?

A. Yes. Two famous ones are the Gunning-Mueller Fox Index and the Rudolf Flesch Reading Ease Formula. The Fog Index appears to be more widely used today.

Q. Would you explain how it works?

A. Take a group of words and count them until you come to the 100th word. If it's in the middle of a sentence, go to the end of the sentence and count the number of words above 100.

Then, count the number of sentences in those 100 or so words and divide that number into the number of words to get an average number of words per sentence.

Next, count the number of words of three or more syllables in the first 100 words. Don't count proper nouns, combinations of short words such as "bookkeeper" or "manpower," or the number of verbs made into three syllables by adding "-ed" or "-es."

Next, add the average number of words per sentence to the number of words with three or more syllables in the 100-word sample.

Finally, multiply the sum by .4.

Consider this example: 12 words per sentence plus 17 words of three or more syllables equals 29. Multiplying 29 by .4, you get 11.6, the grade level of the sample.

Keep in mind that the average American reads on the 9th-grade level and that college graduates tend to struggle with anything above the 16-grade level. Note: Many people prefer to read one or two grade levels below their maximum attainable level. We call that the "comfort level." Some writers aim for this level.

Q. But won't following a formula tend to shackle your writing?

A. Don't follow the formula while writing. Go ahead and write freely. Use the formula to check your writing when you edit it. If the fog is too high, edit heavily. The more often you apply the formula when you edit, the more adept you'll become at incorporating its principles into the normal writing skills.

Q. Can you suggest an easier way to check your copy for readability?

A. Try these:

1. Restrict 60-70 percent of your words to five letters or fewer. If you do, you'll be on a par with Lincoln's Gettysburg Address and some of Shakespeare's works. A variant: Try for an average of five letters per word. A study of major newspapers disclosed that their stories averaged 5.07 letters per word.

2. Allow no more than two ideas per sentence. As noted earlier, short sentences tend to do this for you automatically. Another thing you can do: Make 60 to 70 percent of your sentences simple ones - those containing just a subject and predicate without additional clauses.

Example: "The cat crossed the street" is a simple sentence containing just one idea. "The large, gray cat crossed the wide street" is still a simple sentence even though it contains several adjectives. But "The cat crossed the street, because she wanted to get home" has two ideas, because it contains a clause.

3. Try to locate a software program called "Grammatik" and another one called "Right Writer." I understand both are able to calculate a Fog Index on a computer. I recently checked with several software retailers and could not locate either one. One retailer said Word Perfect had incorporated one of these programs into its software. If you are unable to locate one, you may be able to find a user who owns one of the original programs.

Q. Are there any formulas for speech writing?

A. Yes. Dr. Irving Fang, a professional writer, devised this one called "The Easy Listening Formula." Here's how it works:

Count each syllable above one per word in every sentence. Strive for a score of 12 or less per sentence. A one-syllable word, such as "how," would not be counted. A three-syllable word, such as "interview," would count as two because it contains two extra syllables.

Example: Consider the sentence "He likes to eat in famous restaurants whenever he goes on vacation." The first five words are not counted because they contain no syllable above one per word. The word "famous" contains one extra syllable, "restaurant" contains two extra, "whenever" contains two extra, and "vacation" also contains two extra." The words "he goes on" contain no extra syllables.

Therefore, the "hearability" score of this sentence is seven – a "hearable" sentence.

In case you haven't realized it, this formula penalizes you for long sentences as well as for long words, in this sense: The longer sentences offer an opportunity to include more long words.