The rhetorical purpose of the first 30 lines of Sir Gawain and the Green Knight is that the poem conveys a purpose. The poem uses a boat load of alliteration in almost most of the first 30 lines. “So monstrous a mount, so mighty a man in the saddle”, is one fantastic alliteration that is used. The 18th line has the letter “M” repeated 4 times in a sentence, which makes it as alliteration. Another alliteration used in the poem is in line 12. “Now a thread of hair, now another thread of gold”. In the poem, in lines 20-24 is something called bob and wheel. Bob and wheel is basically just rhymes. “His eyes, like lightning, flashed, And it seemed to many a man, That any man who clashed With him would not long stand.” Flashed