This is a VERY common error.
‘Walking down the street, a car cut across Betsy’s path.’
Can you see what’s wrong with this sentence? In the first phrase, ‘walking down the street’, the (implied) subject is Betsy. In the second phrase, however, we find that the car is the subject. What the author intends to say is that Betsy is walking and the car is cutting across her path – but what they’re actually saying is that the car is walking down the street and cutting across Betsy’s path. Rephrased: ‘As Betsy walked down the street, a car cut across her path.’
Obviously, in this instance we know what the author means to say, and many readers would skim it without noticing the grammatical blunder. But sometimes sentence constructions like this cause confusion, and sometimes they even make for ridiculous reading. Here’s one I came across recently: ‘Sweeping across the paddock, Fran's eyebrows rose as she saw him approach’. Unless I’m mistaken, the author is not trying to tell us that Fran's eyebrows were sweeping across the paddock; I'm pretty sure Fran's eyes were sweeping and her eyebrows were rising. But that’s not how it’s written.
A ‘modifier’ is a word or phrase that adds a description (‘Walking down the street’ in my first example). This grammatical fault is called a ‘dangling modifier’ because the subject of the modifying phrase is missing, leaving the modifier dangling. You might also see it called a ‘dangling participle’.
About this blog
Through my experience as an editor, a reader and a book reviewer, I’ve noticed that some writing faults keep just popping up again and again. As an author, I’m especially aware of those writing crimes that I’m frequently tempted to commit myself. This series of brief tips addresses the common writing problems that I’ve encountered. Following them will help make your writing clear, accurate and stylish.