The methods of measuring unevenness of gravels,laying multiple-orifices filter blocks and stainless nets during the filter reconstruction were used in four water purification plants in Yokohama to assure the normal and effective operation of the filters.是什么意思_The methods of measuring unevenness of gravels,laying multiple-orifices filter blocks and stainless nets during the filter reconstruction were used in four water purification plants in Yokohama to assure the normal and effective operation of the filters.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句