Complex sentence: Soon afterwards, she was heavily hit by American gunfire and sank early in the action near Savo Island at position, with the loss of all but eighteen crewmen (out of a total complement of 197), which were later captured by U.S. forces.
Split into simpler sentences: Soon afterwards, she was heavily hit by American gunfire and sank early in the action near Savo Island at position, with the loss of all but a few of her crewmen. Only eighteen crewmen (out of a total complement of 197) survived the sinking of "Akatsuki" and were later captured by U.S. forces.