Prose is structured using self-contained sentences; it seeks no parallel forms, and eschews rhyme. In fact, it is close to natural speech. However, because speech changes relatively quickly, speech which is written down tends to become conservative and standardized compared to the spoken word. The works of the literary masters of a previous generation then become the models, and so the language of prose shows the phenomenon of being anchored in a form that has departed from the spoken one, and as time passes this disjuncture becomes more pronounced.