Their principal function is to bring about the removal of foreign, dead or degenerating material.
He did all that was in his power to do to prevent his authority from degenerating into tyranny.
But when this habit becomes the characteristic of any wit, it is impossible to prevent it from degenerating into occasional buffoonery, and from supplying a cheap and ready resource, whenever the true vein of humour becomes thin or rare.
For although there was at that time a recognized poetical style, already degenerating to mannerism, a developed prose style did not exist.
The main roads centring in Seoul are seldom fit even for the passage of ox-carts, and the secondary roads are bad bridle-tracks, frequently degenerating into "rock ladders."