Dangling modifier

A dangling modifier is an ambiguous grammatical construct, whereby a grammatical modifier could be misinterpreted as being associated with a word other than the one intended or with no particular word at all. For example, a writer may have meant to modify the subject, but word order makes the modifier seem to modify an object instead. Such ambiguities can lead to unintentional humor or difficulty in understanding a sentence in formal contexts.

A typical example of a dangling modifier is illustrated in Turning the corner, a handsome school building appeared. The modifying clause Turning the corner is clearly supposed to describe the behavior of the narrator (or other observer), but grammatically it appears to apply to nothing in particular or to the school building. Similarly, in At the age of eight, my family finally bought a dog, the modifier At the age of eight "dangles", not attaching to the subject of the main clause (and possibly implying that the family was eight years old when it bought the dog, or even that the dog was eight when it was bought, rather than the intended meaning of giving the narrator's age at the time).

As an adjunct, a modifier clause is normally at the beginning or the end of a sentence, and usually attached to the subject of the main clause, as in "Walking down the street (clause), the man (subject) saw the beautiful trees (object)." However, when the subject is missing or the clause attaches itself to another object in a sentence, the clause is seemingly "hanging" on nothing or on an entirely inappropriate noun. It thus "dangles", as in these sentences:

Walking down Main Street, the trees were beautiful. Reaching the station, the sun came out.

In the first sentence, the adjunct clause may at first appear to modify "the trees", the subject of the sentence. However, it actually modifies the speaker of the sentence, who is not explicitly mentioned.

In the second sentence, the adjunct may at first appear to modify "the sun", the subject of the sentence. Presumably, there is another, human subject that did reach the station and observed the sun coming out, but since this subject is not mentioned in the text, the intended meaning is obscured, and therefore this kind of sentence is incorrect in standard English.

Strunk and White's The Elements of Style provides another kind of example, a misplaced modifier (another participle):

I saw the trailer peeking through the window.

Presumably, this means the speaker was peeking through the window, but the placement of the clause "peeking through the window" makes it sound as though the trailer were doing so. The sentence can be recast as, "Peeking through the window, I saw the trailer."

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