Complex sentence: It stayed in the United States naval fleet until 1966 when it was purchased by the Chilean government; it was later decommissioned in 1994, but was used one last time as a training target and sunk.
Split into simpler sentences: It stayed in the United States naval fleet until 1966 when it was purchased by the Chilean government. It was decommissioned in 1994, and used one last time as a training target and sunk.