Complex sentence: For the next fifteen years he worked in Northern Italy, especially Milan, Venice, Genoa, Padua and Turin, and also visited London on several occasions between 1778 and 1791.
Split into simpler sentences: For the next fifteen years he worked in Northern Italy, especially Milan, Venice, Genoa, Padua and Turin. Pacchierotti also visited London on several occasions between 1778 and 1791.