BRIDGETOWN, Barbados — The United States advanced to the regional semifinals of qualifying for the 2010 World Cup with a listless 1-0 victory over Barbados on Sunday. Eddie Lewis scored in the 21st minute off a through ball from 19-year-old Freddy Adu, who started his first World Cup qualifier. The Americans, seeking their sixth straight World Cup berth, will be joined in the regional semifinals by Guatemala, which defeated St. Lucia on 9-1 aggregate.