We will briefly note the elements mentioned by those who analyse style, and then pass on to concrete examples.
Arrangement of words in a sentence. The first requirement is that the arrangement of words should be logical, that is grammatical. The rhetorical requirements are that—
1. One sentence, with one principal subject and one principal predicate, should try to express one thought and no more. If we try to mix two thoughts in the same sentence, we shall come to grief. Likewise, we shall fail if we attempt to mix two subjects in the same paragraph or composition.
2. The words in the sentence should be arranged that those which are emphatic will come in the emphatic places. The beginning and the end of a sentence are emphatic positions, the place before any mark of punctuation is usually emphatic, and any word not in its usual place with relation to the word it modifies grammatically is especially emphatic. We must learn the emphatic positions by experience, and then our instinct will guide us. The whole subject is one of the relative values of words.
3. The words in a sentence should follow each other in such a simple, logical order that one leads on to another, and the whole meaning flows like a stream of water. The reader should never be compelled to stop and look back to see how the various ideas “hang together.” This is the rhetorical side of the logical relationship which grammar requires. Not only must grammatical rules be obeyed, but logical instinct must be satisfied with the linking of idea to idea to make a complete thought. And the same law holds good in linking sentences into paragraphs and paragraphs into whole compositions.
These three requirements have been named Unity, Mass, and Coherence.
The variations in sentences due to emphasis have given rise to a rhetorical division of sentences into two classes, called loose and periodic.
A loose sentence is one in which words follow each other in their natural order, the modifiers of the verb of course following the verb. Often many of these modifiers are not strictly necessary to complete the sense and a period may be inserted at some point before the close of the sentence without destroying its grammatical completeness. The addition of phrases and clauses not strictly required constitutes looseness of sentence structure.
A periodic sentence is one which is not grammatically or logically complete till the end. If the sentence is somewhat long, the mind is held in suspense until the last word is uttered.
Example. The following is a loose sentence: “I stood on the bridge at midnight, as the clocks were striking the hour.” The same sentence becomes periodic by transposition of the less important predicate modifiers, thus—“At midnight, as the clocks were striking the hour, I stood on the bridge.”