Complex sentence: She appeared with such singers as Mario Lanza, bass Ezio Pinza, tenor Nino Martini, and Japanese soprano "Hizi Koyke", who was one of the first Asian singers to perform "Madama Butterfly" in major opera productions in the United States.
Split into simpler sentences: She appeared with such singers as tenor Mario Lanza, bass Ezio Pinza, tenor Nino Martini, and Japanese soprano "Hizi Koyke". Miss Koyke was one of the first Asian singers to perform "Madama Butterfly" in major opera productions in the United States.