sentences:  They arrived off Kerama Retto, Okinawa Gunto, on the 25th and immediately began sweeping minefields around that stepping-stone to Okinawa.For the next three months, "Signet" swept mines, patrolled, screened transports, fought off air attacks, and supported ground troops.Up until 7 April, her gun crews had to content themselves with watching their sister ships and combat air patrols splash Japanese planes.