阅读理解。 Robert Todd Duncan was born in 1903 in the southern city of Danville,Kentucky.His mother was his first music teacher.As a young man,he continued his music study in Indianapolis,Indiana. In 1930,he completed more musical education at Columbia University in New York City.Then he moved to Washington.For fif years,he taught music at Howard University inWashington.At that time,not many black musicians wereknown for writing or performingclassical music.Teachingat Howard gave Duncan the chance to share his knowledgeof classical European music with a mainly black student population.He taught special ways to present the music.These special ways became known as the Duncan Technique. Besides teaching,Duncan sang in several operas with performers who were all black.But it seemed that he always would be known mainly as a concert artist.However,his life took a different turn in the middle 1930s.At that time,the famous American music writer George Gershwin was looking for someone to play a leading part in his new work Porgyand Bess.The music critic (评论家) of the New York Times newspaper suggested Todd Duncan.Duncan had almost decided not to try for the part as he knew it would not be easy to get it.But he changed his mind.He sang a piece from an Italian opera for Gershwin.He had sung only a few minutes when Gershwin offered him the part.He became famousbecause of the part in Porgy and Bess. Todd Duncan gained fame as an opera singer and concert artist.But his greatest lovein music was teaching.When he stopped teaching at Howard,he continued giving singinglessons in his Washington home until the week before his death. 1．What is this passage mainly about? A．What Robert Todd Duncan loved most.B．How Robert Todd Duncan became famous.C．Robert Todd Duncan and his works of music.D．A brief introduction to Robert Todd Duncan. 2．According to Paragraph 2,while teaching at Howard University,Duncan________. A．found special ways to present musicB．opened doors for other black classical singersC．had the chance to know many famous black musiciansD．became known for writing and performing classical music 3．What happened to Duncan in the middle 1930s? A．He gave up teaching at Howard University.B．He was introduced by the New York Times in detail.C．He was asked to be in charge of the opera Porgy and Bess.D．He was given a big opportunity to become an opera singer. 4．We can infer that Robert Todd Duncan didn't at first want to try for the part mainlybecause________. A．he was too busy to do itB．he was not interested in itC．he was not confident enoughD．he didn't want to become famous 5．Based on the passage,what did Robert Todd Duncan love most? A．Singing in concerts.B．Writing music.C．Singing opera.D．Teaching music