Ted Hughes uses strong descriptive language to create an oppressive atmosphere in "The Rain Horse." As the unnamed man is attacked by a relentless horse in the woods, he is beset by both the horse itself and by the rain:
He saw the rain pulling up out of the distance, dragging its grey broken columns, smudging the trees and the farms.
As he watched it, the horse ran up to that crest, showed against the sky -- for a moment like a nightmarish leopard -- and disappeared over the other side.
In blinding rain he lunged through the barricade of brambles at the wood's edge. The little crippled trees were small choice in the way of shelter, but at a sudden fierce thickening of the rain he took one at random and crouched under the leaning trunk.
The horse was almost on top of him, its head stretching forwards, ears flattened and lips lifted back from the long yellow teeth. He got one snapshot glimpse of the red-veined eyeball... then he was away up the slope, whipped by oak twigs as he leapt the brambles and brushwood, twisting between the close trees till he tripped and sprawled.
(Hughes, "The Rain Horse," Amazon.com -- emphasis mine)
The bolded words and phrases show how Hughes uses language to create a small, oppressive place where the man is trapped. He has nowhere to go because of the "close trees" and "barricades of brambles," and the "blinding rain" keeps him from seeing further. The horse is a ghost, attacking with guerrilla intensity and without reason or purpose. Each powerful phrase and metaphor shows how small and helpless Man is against Nature, and how Man must strive to survive in an unreasoning world.