All madrigals have a Fa-la-la chorus?

False. Not all madrigals have a Fa-la-la chorus. Madrigals are a type of vocal music that originated in Italy in the 16th century. They are usually polyphonic, meaning that they have multiple independent melodies sung at the same time, and they often have a pastoral or amorous theme. Some madrigals do have a Fa-la-la chorus, but this is not a defining characteristic of the genre.