In D.H. Lawrence's "The Rocking-Horse Winner", what would be the element of language within the short story?
You might find it more useful to specify what precisely you are referring to by "language" - do you mean diction (word choice) or another aspect, for example the way irony is built into the text? You might find it useful just to try to analyse the first paragraph and see how Lawrence uses his descriptive powers to set the scene:
There was a woman who was beautiful, who started with all the advantages, yet she had no luck. She married for love, and the love turned to dust. She had bonny children, yet she felt they had been thrust upon her, and she could not love them. They looked at her coldly, as if they were finding fault with her. And hurriedly she felt she must cover up some fault in herself. Yet what it was that she must cover up she never knew. Nevertheless, when her children were present, she always felt the centre of her heart go hard. This troubled her, and in her manner she was all the more gentle and anxious for her children, as if she loved them very much.
This introduction to the story is interesting for a number of reasons, but one is the way that Lawrence introduces irony. We see that although the woman was "beautiful" and started "with all the advantages", the absence of luck is what has made her life radically different from what she had expected. Although she is fortunate enough to have "bonny children" she finds it impossible to love them. However, feeling this inability, she tries to overtly over-compensate, so others think she is such a devoted mother, whilst all the time the centre of her heart is "hard". This secret is just shared between the mother and her children, who she feels always look at her "coldly, as if they were finding fault with her."
Lawrence uses the language in this first paragraph to therefore build up an ironic picture of the mother, setting the stage for her relationship with Paul and the dynamics that will come to dominate the novel.