AN OTIMUM DESIGN OF THE SINGLE--STAGE UNDERGROUND DRAIN PIPE SYSTEM OF THE IRRIGATED AREA IN THE AREA OF THE BEND OF THE YELLOW RIVER IN NINGXIA是什么意思_AN OTIMUM DESIGN OF THE SINGLE--STAGE UNDERGROUND DRAIN PIPE SYSTEM OF THE IRRIGATED AREA IN THE AREA OF THE BEND OF THE YELLOW RIVER IN NINGXIA在线翻译_英语_读音_用法_例句