And this is what they saw:

The tag that introduces almost every set-piece poem in the novel. It is a cue to the audience that the prose is about to stop and the verse begin.

Plum on the ridge about to break its jade; water in the pool slowly turning to ice.

The plum blossoms in the cold, so its opening buds are the first sign of deep winter, not of spring. 將 is jiāng, on the point of doing something. The jade being broken is the bud case splitting — the flower is the white stone coming out.

Red leaves have all drifted down; the green pine grows fresher still.

更 is gèng, even more, not the gēng that means a watch of the night. The parallel line settles it: 漸 jiàn in the couplet above sits in exactly the same slot and is plainly an adverb, so this one is too. The point of the pair is the old contrast — everything showy falls, and the plain evergreen looks better for it.

Pale clouds fly as if to snow; withered grass lies flat along the hills.

伏 fú is to crouch or lie prone — the grass has gone down under the frost, and the hillside reads as level because nothing is standing up on it.

Cold light everywhere, and far; a gloom that goes through to the bone.

陰陰 yīn yīn is a doubled word, and doubling in Chinese verse thickens rather than repeats — gloom on gloom. The line closes the poem on the body, which is where the next line of prose picks it up.