What is the main difference between Sandburg’s "Fog" and Frost’s "Mending Wall"? "Fog" uses everyday language, while "Mending Wall" does not. "Fog" uses metaphor, while "Mending Wall" does not. "Mending Wall" is in a modern format, while "Fog" is not. "Mending Wall" is in free verse, while "Fog" is not.