I don't see the underline, but I'm pretty sure that the verb is "has known". That's the present perfect tense.
This is the rhyme scheme in this poem: ABBAABBACDCDCD.
What this means is that each letter which is repeated rhymes with each other. So A refers to lines 1, 4, 5, and 8, which all rhyme. B refers to lines 2, 3, 6, and 7, which all rhyme. C refers to lines 9, 11, and 13, which all rhyme. D refers to lines 10, 12, and 14, which all rhyme.
I think it’s true I’m not 100% sure I’m 90% sure