Brooks is dropping some perfect rhymes here, so listen up. We talked about the rhyme scheme in the "Form and Meter" section. It propels the poem along, like a strong and steady freight train. But that's just the tip of the iceberg (or, sound-berg, if you will).
First up, we can say what's lacking in this poem in terms of sound: complexity. Our ear doesn't catch on overly long or obscure words. Brooks isn't trying to use ornate language. It's straightforward music, designed to ground our ear in the common, mundane struggle of life in a kitchenette building. On both a content and a sonic level, we can hear it loud and clear.
That's not to say, though, that Brooks gives up on using sound in other, interesting ways. If you look closely, you'll notice a heaping helping of alliteration here. You want examples? We thought you'd never ask. Just check out line 5: "fight with fried potatoes." Here those F sounds ("fight" and "fried") so closely together? That forces (see what we did there?) the air between our bottom lip and teeth, giving us a subtle sense of the friction that this line is describing.
We also notice a lot of W words in this relatively short poem. Clearly, since the poem is told from the collective speaking voice of "we," that word pops up quite a bit. But, beyond that, we get "we were willing" (8), "warm it" (9), "We wonder" (11), and "We think of […] water" (13). So… what's up with that? In a way, this W alliteration seems a kind of sound-based callback to the central W word of the poem: "We." With its collective speaker, this poem is making the case that we're all in this together. It may not be so surprising, then, to see all these W words popping up all over the place, reminding us that "we" are many, not few, and that we're all in this thing (which we might call the daily struggle for hope) together.