"The Road Not Taken" by Robert Frost is divided into four five-line stanzas, with the breaks between stanzas indicated by blank lines. The rhymes in the poem form a regular pattern, with each stanza having an identical rhyme scheme. The rhyme words occur at the ends of the lines, and are mostly regular in that they repeat both a vowel and a consonant sound.
Literary critics usually describe rhymes by indicating the rhyme sounds with capital letters, with the first rhyme sound of a stanza assigned an "A", the second a "B", the third a "C", etc. When the same sound recurs, critics repeat the letter. Thus in the first stanza, one would label the rhyme scheme as follows (rhyme words italicized and labels bolded):
Two roads diverged in a yellow wood, A
And sorry I could not travel both B
And be one traveler, long I stood A
And looked down one as far as I could A
To where it bent in the undergrowth; B
Thus the rhyme scheme of the stanza is described as "ABAAB".
All four stanzas of the poem use the same rhyme scheme, albeit with different rhyme words. The rhyme words are all the final words of the lines, and are thus known as "end rhymes".