An apparatus for receiving broadcast signals includes a receiver to receive broadcast signals including service guide fragments which are used to announce information for the broadcast signals, the service guide fragments including a service fragment describing a service of the broadcast signals and a content fragment describing a content of the service, the content fragment including an extension element having a component element describing a component included in the content and a capability element representing capabilities required for decoding and presenting the content, the component element an audio component element representing a role of an audio component of the content and a video component element representing a role of a video component of the content data, a decoder configured to decode the content and the service guide fragments; and a display unit configured to display the content with a sign language content.