Essentially, a sentence’s introductory bit and its main bit need to fuse correctly. Or, as I like to think of it, they need to talk to each other. If a sentence begins “Flipping restlessly through the channels,” then the sentence’s subject—more than likely, its very next word—has to tell us who’s holding the remote. It might be “I,” it might be “he,” it might be “Cecilia,” but it’s certainly not “John Huston’s The Treasure of the Sierra Madre.” Strolling through the park, the weather was beautiful. Nope. The weather was beautiful as we strolled through the park. Yup.
