The knights of the round table express their solidarity by wearing a green gridle as gawain does. why does gawain wear the green girdle

Gawain wears the green girdle as a symbol of his weakness. He behaved deceitfully and returned to Camelot bearing the girdle as a symbol of his failure in keeping his vow.

Taking into account that alliteration can be defined as the repetition of initial consonant sounds in successive words, and assonance can be defined as a literary device that uses similar sounds in close syllables or words, the excerpt that uses both alliteration and assonance within this list is:

Though two, close-keeping, are lass and lad,—