Through more than a month of rehearsals, Tsao spent time every day with a voice teacher. From his habitual singing from the throat he gradually shifted over to singing from the diaphragm, getting resonance from the head.
排了一個多月，曹復永每天跟著聲樂老師摸索，從習慣性的喉腔音慢慢轉換到胸腔音，用丹田使力，顱腔共鳴。