Complex sentence: Then, in 1920 Okinawa was hit hard by a major economic downturn, the price of cotton and silk fell by 70% in some areas and it was still recovering from a major epidemic that swept through the islands.
Split into simpler sentences: Then, in 1920, Okinawa was hit hard by a major economic downturn. The price of cotton and silk fell by 70% in some areas and it was still recovering from a major epidemic that had swept through the islands.