The headline of this post is an example of a misplaced modifier (more specifically, this one is a dangling participle). Misplaced modifiers pop up every day, and even though it’s often clear what the writer meant, they cause a little stumble — and occasionally major confusion — for the reader.
Why it’s wrong: When you “back into” a sentence with a phrase, the information in that phrase goes with the subject of the sentence. So here, the “having started this post” goes with “an idea,” which is not right — it belongs with “me.” Sometimes sentences start with a phrase that doesn’t belong with anything in the sentence, which can really confuse readers.
How to spot one: Anytime you have a sentence that begins with a phrase — an adjective phrase, a prepositional phrase, a participial phrase — make sure that phrase goes with the subject.
How to fix it: You may be able to simply move the modifying phrase closer to what it modifies, or you may need to rewrite the sentence. With a dangling participle, it’s often better to change the participial phrase to a subordinate clause, which is what works for the title of this post: “As I started this post, an idea struck me.”
Here are a couple more examples: