writing a letter with *one's own hand / write a letter with *one's own hand

thickly wooded / with highly standing trees

deepening <silent> / with calm and deep advance

calm / deep / advanced / deeply

piercing cold / chill to the bone / getting chilly

deeply cold / piercingly cold

deep / absorbing

deep / absorbing

(of the way in which things progress or move) nimbly / (of the way in which things progress or move) smoothly / (of the way in which things progress or move) easily / (of the way in which things progress or move) lightly / (of the way in which things progress or move) without any difficulty

serve as a retainer / be a subject of