Everyone is familiar with the phrase “dangling modifier,” but hardly anyone knows what it means. A dangling modifier is a word or clause that modifies a word it should not, logically, modify.
For example, "Walking down the street, my hat blew off my head." It kinda sorta seems like it's sorta kinda right. Read it again s-l-o-w-l-y, though.
In fact, it says that my hat was walking down the street (“walking down the street” is attached to “my hat”), a neat trick I’d like to see but for now, anyhow, grammatically - and millinarily* - unsound.
A better way to write this sentence: As I walked down the street, my hat blew off my head.
The takeaway here: Make sure that a clause meant to modify a word in a sentence is attached logically to that word.**
* Yes, I made up that word, but you got it, right?
** As always, there are exceptions, phrases so common that they’re permitted to dangle. The most common may be “generally speaking,” as in “generally speaking, blondes have more fun.” Blondes aren’t doing the speaking, but the listener gets it anyhow.