Zaide

Zaide is an unfinished opera, K. 344, written by Wolfgang Amadeus Mozart in 1780. Emperor Joseph II, in 1778, was in the process of setting up an opera company for the purpose of performing German opera. One condition required of the composer to join this company was that he should write a comic opera. At Salzburg in 1779 he began work on a new "rescue" opera, Zaide. It contains spoken dialogue, which also classifies it as a Singspiel (literally, "singing play").
See more at Wikipedia.org...