A language conversion system, capable of creating and changing content easily, is provided. A DRM agent obtains the license from a first SRM, and sets the license to a forwarding state locally; the DRM agent deducts one permission of moving the license; and the DRM agent sends the license to a second SRM. The driven component is connected to, or is in supporting relation with, the mattress support, so that a height of the mattress support above a floor surface is settable and continuously adjustable by means of at least one actuator associated with the at least one drive unit. A phase difference between the first and second oscillation signals satisfies a predetermined relationship.