sentences:  Shortly afterwards, the 58th/59th Infantry Battalion replaced the 25th in occupation of the knoll, while the 24th Infantry Battalion resumed the advance along the Buin Road on 17 April, subsequently taking part in the fighting along the Hongorai River.The 9th Infantry Battalion, however, was not withdrawn immediately, and remained in the northern area until it handed over to the 57th/60th Infantry Battalion in early May.The fighting on Bougainville continued throughout April as the Japanese resisted the Australian advance and went on until July when the fighting petered out due to heavy rain and flooding.