Reviewed by Katherine Foran
Extension Communications and Marketing

Principle 1
Keep sentences short

Sentences must vary in length to avoid boring your reader. But the average length should be short. Fifteen to 20 words per sentence would be a good average.

Sentences are getting shorter. Average shrinkage of sentences in English prose from Elizabethan times to 1900 was from one-half to two-thirds. The trend continues, although more slowly.

Short sentences are not enough by themselves. Long sentences are not the chief cause of foggy writing. Fuzzy words block clarity.

Trim the fat from your writing. Fuzzy words, along with unnecessary ones, make your writing difficult to read and understand.

Control sentence length by noticing the number of lines in each sentence. A typewritten line, or a line in average handwriting, averages 10 to 12 words. Remember to vary sentence length, but worry about those that run more than two lines.

Principle 2
Prefer the simple to the complex

This principle does not outlaw the use of a complex form. You need both simple and complex forms for clear expression. At times, the complex form may be best. So, if the right word is a big word, go ahead and use it. But if a shorter word does the job, use it.

Of the 10 principles, complexity is the one most violated. Nearly anyone facing a sheet of blank paper begins to put on airs. We use three words where one would do. We can't resist the gingerbread of four-syllable words. We write "utilization" when we could just as well write "use," or "modification" when the short word "change" would do.

Unconscious use of complexity is hard to overcome. The roots of the fault are sunk deep in habit.

Writing shorter sentences usually means you use shorter words.

Principle 3
Prefer the familiar word

You need all the words you can master. Perhaps you can get along with a working vocabulary of 5,000 words. But if you want to succeed in our complicated society, you'll be better off with 30,000. However, intelligent people use their large vocabulary only to give clear, exact meaning — never to show off.

The most familiar words are 10 short ones: the, of, and, to, a, in, that, it, is, I. They make up 25% of all that is written and spoken in English.

The 50 words most often used make up 50% of written English. The 1,000 most common words turn up 80% of the time and the 10,000 words most often used account for 98 percent of all that is written. Remember, there are more than 500,000 words in Webster's Unabridged Dictionary.

Principle 4
Avoid unnecessary words

Many communications can be cut in half and still say the same thing.

Unnecessary words usually are included unconsciously.

One minute spent organizing a mass of details will save several minutes in its writing. Furthermore, a few minutes spent in going over copy and correcting and editing it will also pay off.

Principle 5
Put action in your verbs

"The fullback hits the line." That's writing with an active verb. "The line is hit by the fullback." In this sentence the verb is passive. The electricity has gone. The snap of action is no longer there. The same idea translated into typical business jargon goes something like this: "The hitting of the line is an activity engaged in by the player acting in the capacity of fullback."

It is better to say "the bull sprang into the sale ring" than to say he "came into the ring quickly" or "came in with a quick jump."


Present design methods are predicated on the assumption that one-piece windshields are preferred by the public.


At present, designers assume the public prefers one-piece windshields.


When an application of wax is made to this surface a brilliance is imparted to it.


Waxing this surface brightens it.

Principle 6
Write like you talk

Some grammarians would insist that "write like you talk" is poor grammar. They prefer "write as you talk." But this violates the rule "write like you talk."

"Write like you talk" has its limitations. Most of us do talk rather untidy English. We repeat ourselves. We pause. We hesitate. However, in our speech we do not use long, involved sentences laden with multi-syllable words that often occur in our writing.

"Write like you talk" also has its limitations when it comes to news writing. Some newspapers still prefer that news stories be written in inverted pyramid style and in an impersonal manner.

Principle 7
Use terms your reader can picture

Avoid fuzzy words. "Conditions," "situations," "facilities," "inadequacies" are typical examples.

An engineer might say an alloy is "not fabricable." This is a general term that might mean several things. When asked for a more specific meaning, the engineer might say "the alloy cracks when it is cold-rolled."

Principle 8
Tie in with your reader's experience

Much communication fails because writers ignore readers' beliefs, ignore how they came by them, and how firmly they hold them.

Words are not fixed. They vary in meaning from person to person, the meaning depending upon the experience of that person and the pictures the words call to mind.

Highly abstract terms often are useful for thinking, but they are tricky in communication because they are open to such wide interpretation.

In trying to persuade readers to accept your words, remember that the meaning they give them will be determined entirely by their past experience and purposes.

To get your words read, understood and accepted, you must have a clear understanding of your own purposes and of the purposes of the reader. If these purposes differ, you have two courses for winning acceptance of your message. You must either change your readers' purpose, or you must show them that though your purposes differ in part, they have, at the same time, much in common.

In writing, don't get lost in details.

It isn't enough to write so you will be understood. You must write so you can't be misunderstood.

Principle 9
Make full use of variety

The style of your writing will grow as you grow.

Good writers work within a strict discipline of simplicity. But they introduce enough variety of sentence length, structure, and vocabulary so that the simplicity is not noticed. As a result, readers never think the writing is choppy or childish.

Variety is a main ingredient in the art of writing. Only practice can lead to the facility that produces variety. Being aware of the point, however, helps one gain facility more rapidly.

Principle 10
Write to express, not impress

A trap awaits the inexperienced writer. When writing, we often try to impress rather than express. We try to be someone else.

No writing is easy. But we make it more difficult by seeking out long, unfamiliar words, and in writing long, meandering sentences.

Few are fooled by fancy language. It's been a long time since any of us have heard anyone say, "I can't understand what he is saying; he must be highly intelligent."

Don't be awed by the rules of grammar. Pay attention to clear expression, and for the most part grammar will take care of itself.

Fog indexes

If you want to test the clarity of your writing, you may wish to consider using a "fog index." Fog indexes measure the complexity of writing samples, and often provide a means of calculating the reading or educational level required to understand a particular passage. Some fog indexes are available as computer software programs, or you may do the calculations yourself. Here is an example of a fog index you might try:

The Gunning Fog Index

  • Select a sample at least 100 words long. Divide the total number of words in the sample by the number of sentences. This gives the average sentence length of the sample.
  • Count the number of words with three or more syllables in the sample. Don't count words (a) that are capitalized; (b) that are combinations of short, easy words (such as "bookkeeper" or "butterfly"); (c) that are verb forms made into three syllables by adding -ed or -es (such as "created" or "trespasses"). Divide the total of such words by the number of words in your sample: for example, 15 long words divided by a sample 100 words long gives you 15 percent hard words in the passage.
  • To get the fog index, add the sentence length and percentage of hard words. Multiply this total by 0.4. The answer corresponds to the years of education needed to easily understand the piece of writing.

Texts for a wide audience generally need a fog index less than 12. Texts requiring near-universal understanding generally need an index less than 8.

It is important not to over-use the fog index. Use it only occasionally to spot-check your writing. Don't write to make a good fog index score. That will make you write short, choppy sentences. Like these.

Instead, learn and practice using the "Ten Principles of Clear Statement." If you observe these guides to good writing, your writing will naturally grow easier to understand.

The Gunning Fog Index and Ten Principles of Clear Statement are copyrighted by Gunning-Mueller Clear Writing Institute, Inc., and may not be reprinted or adapted without prior written permission.

Adapted from "The Technique of Clear Writing," revised edition New York: McGraw-Hill Book Company, 1973. Used with written permission of the author and of the copyright owner, Gunning-Mueller Clear Writing Institute, Inc., Santa Barbara, Calif. 93110.
Publication No. CM201