Complex sentence: In Okinawa the sai was used by domestic police ("ufuchiku") to arrest criminals and for crowd control, the use of the sai was perfected in 1668 by Moto Chohei, an Okinawan prince.
Split into simpler sentences: In Okinawa the sai was used by domestic police ("ufuchiku") to arrest criminals and for crowd control. The use of the sai was perfected in 1668 by Moto Chohei, an Okinawan prince.