A modifier is an optional word or phrase that changes the nature of the information in a sentence without altering the sentence’s grammatical structure by its inclusion or omission. The specific varieties of modifier misuse follow.
1. Dangling Modifier
A dangling modifier is one in which the introduced word or phrase seems to be associated with the subject rather than the object, or with nothing. In “A keen observer of popular culture, Smith’s words are as pertinent as they are poetic,” Smith’s words, rather than Smith himself, are said to be a keen observer. To unambiguously make the intended point, the writer should form the “keen observer” comment as a complete clause and conclude the sentence with a separate clause: “Smith is a keen observer of popular culture, and his words are as pertinent as they are poetic.”
2. Dangling Participle
One type of dangling modifier is the dangling participle, in which the sentence element that misleads the reader is, or includes, a participle, a word that appears to be both an adjective and a verb, such as leading in the following example: “Leading the way, the path opened into a clearing.” This sentence errs by not explicitly mentioning the object — in this case a person preceding others as they follow a path that leads to a clearing — and thereby suggesting that the path, rather than a person, led the way.
Depending on the writer’s intent, the sentence should refer to the object in the first person (“As I led the way, the path opened into a clearing”), the second person (“As you led the way, the path opened into a clearing”), or the third person (“As she led the way, the path opened into a clearing”).
3. Disruptive Modifier
A disruptive modifier is one that interrupts the flow of a sentence because it is located between the verb and the object. In “He was instructed to administer every two hours the dosage,” administer and “the dosage” should be adjacent. The modifying phrase, in this case, is best positioned at the end: “He was instructed to administer the dosage every two hours.”
A split infinitive, in which a preposition is separated from a verb by an adverb (“She intended to quickly leave a message”) rather than being in proximity, with the adverb placed elsewhere (“She intended to leave a message quickly”), is a type of disruptive modifier. However, although split infinitives can sound awkward, many writers, recognizing that the traditional prescriptive ban of such constructions was founded on a misguided effort to emulate the supposedly perfect grammar of Latin, consider them acceptable.
4. Misplaced Modifier
A misplaced modifier, because its location in a sentence is erroneous, affects a word or phrase other than the one intended. In the sentence “Do we really want folks who are so easily duped in the White House?” the incorrect implication is that there is a concern about people being deceived while they are located in the White House. But this sentence features a casual reference to the current presidential administration, not to just anyone who happens to be visiting the White House, so the modifying phrase “in the White House” should immediately follow folks and precede the action: “Do we really want folks in the White House who are so easily duped?”
A variation of this problem is caused by the misplacement of a limiting modifier — almost, only, simply, and the like. Only, in the sentence “He wasn’t only listening to tone, but also to the rhythms and patterns” suggests that the subject was doing more to tone than listening to it, but the meaning, which only becomes clear when the entire sentence is read — which becomes clear only when the sentence is read, that is — is that the subject was listening to tone as well as to other qualities. That meaning is expressed in this revision: “He was listening not only to tone but also to the rhythms and patterns.”
5. Squinting Modifier
A squinting modifier, also called a two-way modifier, is a word whose association is ambiguous; it could be modifying a preceding word or a following one. In “Asking the child about it too often results in shrugs,” the writer has failed to communicate whether shrugs occur from too-frequent questions, or whether questions asked with an unstated frequency result in an excessive number of shrugs. One solution is to place the modifier at the beginning of the sentence: “Too often, asking the child about it results in shrugs.”