听力原文： American coast guard officials in Florida say they have returned to Cuba a group of would-be migrants who try to make their way to the United States in an unusual vessel, a floating truck. They said one of their planes spotted the Cubans more than half way through their journey, and the coast guard could not believe their eyes when they saw the vessel. The Cubans had attached floats and propellers to a 1951 shabby truck. What has happened to the Cubans?