Jose Carreras and Sarah Brightman are singing at the Bolshoi tomorrow with all returns to go to repair the famous theatre, Carreras and Karl Scheufele, chief concert organiser, said to a news conference. "I am happy to revisit Moscow and appear on the glorious Bolshoi stage. It is an honour for any singer," said Senor Carreras. He will sing Verdi and Strauss in the first part, and Miss Brightman take most of the second with airs from musicals and operettas. Crowning the concert will be two duos--from Andrew Lloyd-Weber's "The Phantom of the Opera" and Franz Lehar's "The Merry Widow". When asked why Russian classics will be out of the Moscow concert, Jose Carreras said that he had only snatches of spoken Russian--not enough to sing, though he loves the Russian opera and thinks Tchaikovsky is the world's best composer of all times.