In Owen's poem, form does relate to content. Language choices reflect the hard, harsh content discussing Hell: "I knew that sullen hall, / ... I knew we stood in Hell." This connection between language and content is displayed in vocabulary words like "sullen hall" and "stood in Hell" and also "guns thumped ... flues made moan," "something had been left, / Which must die now," and "the march of this retreating world."
Sound is coupled with vocabulary and amplifies the connection between form and content. Owen uses many words with harsh consonants to produce a harsh sound to accompany a harsh vocabulary and topic, for example, the emphasis on /t/ and /d/ in the first line: "It seemed that out of battle I escaped."
The structure also reflects content by its terseness and minimalistic rhythm. The meter is iambic pentameter (rhythm of iambs (x /) in pentameter, which means continuing for five repetitions called feet, x / x / x / x / x /). The curt meter, especially when coupled with the harsh vocabulary, connects the poem's meter to its content.
The structure also displays this connection between form and content. The stanzas seem to be arranged in no apparent order--some are short, some are long--but this jagged stanza structure emphasizes the jaggedness of the experience of war and the other-worldliness of the poetic speaker's experience down the "profound dull tunnel, long since scooped / Through granites ... ."