Singing
Most people can sing notes which cover more than an octave.  People who sing a lot will probably be able to sing over two octaves.  Singers can be called according to whether they have higher or lower voices: soprano, mezzo-soprano and contralto for women, tenor, baritone or bass for men.  Some men are able to train their voices to sing alto by using a falsetto voice.  Children’s voices are often called treble.