It is written as a ballad, which is typically a narrative poem that tells a story and is written in quatrains, or four-line stanzas, with a rhyme scheme. In "Sea Fever," Masefield uses this structure to show a sense of rhythm and repetition that mimics the ebb and flow of the sea. He also uses alliteration in several lines, such as "And all I ask is a tall ship and a star to steer her by" and "And quiet sleep and a sweet dream when the long trick's over." This repetition and use of sound devices, along with the ballad structure, help to reinforce the poem's theme of the speaker's longing for the sea and the freedom and adventure it represents.