The main auditory poetic elements in "The Road Not Taken" by Robert Frost are rhyme and meter. The poem consists of four five-line stanzas with regular end rhymes following the pattern ABAAB.
The meter of the poem is iambic tetrameter, but is somewhat irregular with frequent anapestic substitutions and trochaic inversions, which give it a conversational tone despite frequently end-stopped lines, in which syntactic breaks occur at the rhyme words.
There are a few examples of alliteration, such as "wanted wear", but generally Frost uses very few auditory devices in this poem. The reason for this has to do with his philosophy that a poem should be constructed around "the sound of sense" rather than elaborately artificial sonic patterns. Although Frost approved of meter, famously saying that writing free verse was like playing tennis without a net, he favored a conversation tone.