Then you should have a button which should which ca which can be used for increasing or decreasing the volume.
Mm-hmm.
Then , there should be a button which can give subtitles for a particular program which is going on a television. For example , if you are watching a French program and you would like to have a subtitles in English , then there should be a channel which can trigger this mechanism in the television so that the user can see uh the  the subtitles on the screen.
Mm-hmm.