Prepositional Phrases

Anyone who writes long sentences runs the risk of inadvertently coming up with a confusing or misleading statement. "Bob pet the dog and then he jumped in his car." Does that sentence mean Bob or the dog jumped in the car? We can make an educated guess but perhaps a revision might be in order.

Teacher Sends Boy Home With Feces in Bag. So was boy sent home carrying the bag of feces or was the boy sent home in the dirty bag? Normally, a little confusion makes for a more interesting day but in this case, it's just gross.