An analysis of one’s process of reading silently, that is, to himself, will show that, in reading No. 3-1, he takes note of the commas and their meanings (disconnecting and regrouping), just as he takes note, when reading aloud, of the group depressed (written in a line below) in No. 3-2.
To obtain the real meaning of this sentence when reading silently, he reads it commatically; to impart the meaning when reading aloud, he reads it inflectionally.
Our next illustrative sentence and its variations are not much unlike the sentences just considered; but the relations between some of the words in them are not quite so familiar to young readers:
4. Boys like Henry never fail in school.
The meaning of this sentence is unmistakable, and at no point within it is a mark of punctuation even suggested; but in a similarly formed sentence doubt as to the meaning may arise:
4-1. Boys like men may be courageous for principle’s sake.
“Like Henry” in No. 4 suggests some distinguishing quality that Henry is known to possess,—for instance, diligence. Then, “boys like Henry” means “diligent boys.” But “like men” suggests no particular qualities ascribed to boys; and therefore, if the term “like men” is not applicable to or intended for “boys,” we cut it off by commas. Thus an apparent relation is shown not to be the real relation; and therefore we must regroup the words, seeking the new meaning through our knowledge of the meaning of language thus regrouped. The regrouped sentence will read as follows:
4-2. Boys, like men, may be courageous for principle’s sake.
Regrouping of this kind cannot be automatically made by a writer, or automatically apprehended by a reader, until the meanings of both the unpunctuated and the punctuated language are perfectly familiar to the writer or the reader. One’s familiarity with language need not be purely technical to make it accurate and thorough; but we cannot readily discuss the language of our illustrative sentences without using some technical (grammatical) terms.
“Like men” in No. 4-1 is an adjective, and is in the natural position of an adjective of this kind. “Like men” in No. 4-2 is an adverb, and is out of its natural position, thus readily giving rise to a wrong grouping of the words in the sentence. To prevent such wrong grouping, commas are used; and they will be used by a writer quite automatically when the purpose and effect of such use are understood.