By comparing the siphonic roof storm system with the gravitational drainage system of roof rainwater, the advantages of the siphonic roof storm system are described.是什么意思_By comparing the siphonic roof storm system with the gravitational drainage system of roof rainwater, the advantages of the siphonic roof storm system are described.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句