The basic idea of contemporary metaphor research is that metaphor is defined conceptually as understanding one thing in terms of something else. This has placed the wide variety of linguistic forms of metaphor in second place. A lot of metaphor research does not look into the differences between metaphor and simile, metaphor and extended metaphor, and metaphor and allegory, to  mention the most obviously distinct ways of expressing ‘understanding one thing in terms of something else.’ However, these and other linguistic forms of metaphor exhibit radically different structures and functions (seeStructures and functions of metaphor), and DMT needs to address their varying relation to processing. This requires a solid model of linguistic forms of metaphor that is based in a uniform description of the structures and functions of metaphor.