Word of the Week

Periphrasis

and Periphrastic Genitivitis

or
Are you all strung out on prepositions?

Periphrasis is the expression of an idea by using many words rather than just a few. In periphrastic writing, function words are used instead of inflection.

Function words indicate relationships or grammatical functions; they usually do not contribute to or change the meaning of a sentence. Function words are

• Adverbs and adjectives used to indicate a comparison (more and most)
• Auxiliary, or helping, verbs (to be, to have, to do) used to indicate the time, person, and number of a verb
• Relative pronouns (who, which, that) used to refer from one clause to the preceding one
• Prepositions (e.g., of, for, by, with, in) used to join nouns to other words
• Conjunctions (and, but, or, nor) used to show the relationship of one clause to another

Inflection is the spelling change in a word to indicate its grammatical relationship to other words in the sentence. For example,

1. Forming the plural of nouns requires that an s or es ending be added (horse, horses; car, cars).
2. Forming the past tense for irregular verbs requires that the medial vowel be changed (swim, swam, swum); for regular verbs, it requires that the ed ending be added (walk, walked).
3. Forming the possessive, or genitive, case of nouns requires that 's, an apostrophe ('), or the function word of be added (horse's, Moses', the house of Dr. Clark).

Periphrastic constructions in your writing can be reduced by using nouns as modifiers rather than by using function words. The wording in this sentence

The changes of the axial position of the model in the tunnel are accomplished by means of a split-sting section that can be added to or removed from the model assembly without disconnecting the lines of the instrumentation.

can be reduced to

The axial position changes of the model in the tunnel are accomplished by a split-sting section added to or removed from the model assembly without disconnecting the instrumentation lines.

Removing half the bolded prepositions (function words) made this sentence more easily read and the meaning clearer: nouns and their adjectives now modify other nouns (e.g., axial position is used to modify changes and instrumentation to modify lines).

Changing the sentence to active voice can make it even clearer:

By adding or removing a split-sting section to or from the model assembly, one can change the axial position of the model in the tunnel without disconnecting the instrumentation lines.

Most periphrastic constructions are genitive (possessive). However, in the sentence above, they describe the types of changes and lines. The periphrastic genitive can also indicate the doer of an act--the wind's force (the force of the wind), with the author's permission (the permission of the author), the Pathfinder's launching (the launch of the Pathfinder)--or the recipient of an act--the child's murderer (the murderer of the child), the team's defeat (the defeat of the team).
Using what you have learned, can you improve this sentence?

The user is responsible for assessing and documenting the influence of out-of-tolerance conditions on the validity of present and past data for their effect on the quality of products by this equipment whenever nonconformances are found during calibration.

Make it your practice to delete excess genitive prepositions, but do so in moderation. Just as too many prepositional phrases can muddy a sentence, the opposite extreme, a noun-adjective string that is too long, can make it impossibly obscure. Consider the following preposition-deficient sentence:

NASA's Chief Financial Officer's somewhat controversial and era-ending June 1995 executive notice, Minimum Office Automation Software Suite Interface Standards and Product Standards, concerning inter-Center NASA computer software and hardware interoperability and standardization affected our division chief's recent end-of-the-fiscal-year Sun Unix system mini-mass buying decision.

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Last updated: 1/20/2009