sith > since
3 And shivering spear in bloody field first shook,
shivering > quivering field > field of battle, battle shook > wielded
4 He found himself dishonoured so sore.
He > [Had he]
5 Ah, gentlest knight that ever armour bore,
gentlest > noblest
6 Let not you grieve dismounted to have been, 7 And brought to ground, that never was before; 8 For not your fault, but secret power unseen:
not > [it was not]
9 That spear enchanted was, which laid you on the green!