Mozart was a  (作曲家). He wrote classical music and operas. (他的) music is difficult to play and sing. Musicians and singers (训练) for a long time before they can play and sing Mozart's music, (但是) pop and rock musicians don't train much. Their most popular instrument is the guitar. In America, black musicians often sing (悲伤的) songs. They call this music the blues. Another (种类) of modern music (来自) America is jazz. This music often (使用) trumpets and other loud instruments. We use(钢琴)and violin to play (所有的) types of music.