Where´s the poem? so I can try to help
The purpose of exposition (or expository writing) is not primarily to amuse, but to enlighten and instruct. The objective is to explain and analyze information by presenting an idea, relevant evidence, and appropriate discussion. Its essential quality is clarity.
Assuming I understand the Question,
The answer is Personification or the impersonation of an abiotic object
the particles in solids move slower and tend to be smaller so they are packed in smaller together wich creates the partical to move slower . hope this helped have a nice day .