A trucker driving along on the freeway notices a road sign in the distance that reads 'Low Bridge Ahead.'
Sure enough, the trucker gets stuck under the bridge. Cars are backed up for miles.
Finally, a police officer arrives at the scene. The cop gets out of his cruiser and walks around to the truck driver. He puts his hands on his hips and remarks, "Looks like you got stuck, huh?"
The trucker replies sarcastically, "No, officer, actually I was delivering this bridge and I ran out of gas!"