I have always wondered about the rDzong-kha word for “to do,” which is spelled either as ’bad, sbed, or sbe. But my impression is that both of these are mistakes caused by ignorance. Actually it is the verb byed (“to do”) as in Tibetan (or Chos-skad for political correctness) and the difference in rDzong-kha being only in pronunciation. In rDzong-kha, the subscript (here y-subscript) is silent. Such a phenomenon is not unknown especially in Central Tibetan dialect such as in the pronunciation of sprang, spral, and spre’u.