Pu'd you the rose or lily?
Or came you by yon meadow green,
Or saw you my sweet Willie?"
She sought him up, she sought him down,
She sought him braid and narrow;
Syne, in the cleaving of a crag,
She found him drowned in Yarrow!
Hecht (line 6) means vowed; haughs are water-meadows; and to be twined o' one's marrow, is to be separated from one's loved one.