sentences:  U.S. National Dancesport Champions (Professional Smooth)
  
  The United States national professional ballroom dance champions are crowned at the United States Dance Championships (formerly United States DanceSport Championships, USDSC, and United States Ballroom Championships, USBC), as recognized by the National Dance Council of America (NDCA) and the World Dance & DanceSport Council (WD&DSC).The American Smooth division consists of American-style waltz, tango, foxtrot, and Viennese waltz.