Simplify the following text for a Grade 9 native English-speaking person.
Original: Piccinni 's first opera , Le donne dispettose , was produced in 1755 , and in 1760 he composed , at Rome , the chef d' Å `` uvre of his early life , La Cecchina , ossia la buona Figliuola , an opera buffa with a libretto by Goldoni , which `` enjoyed a two-year run in Rome and was played in all the important European capitals .
Simplified: His opera La Cecchina , ossia la buona Figliuola with a libretto by Goldoni played for two years in Rome and was produced in all the important European capital cities . It was probably the most popular opera buffa of the 18th century .