We no longer want to be bothered with the moral dissertations of which the eighteenth century was so fond, nor with the lengthy descriptions of scenery which were favoured in the nineteenth. When the novel became realistic authors fell in love with detail for its own sake, and it took them a long time to discover that detail is interesting only if it is relevant. 1.what is the feature of literature works in the eighteenth century and the nineteenth century respectively? 根据这句话回答。 2.paraphrase the underlined sentence.