dualsn.双排气管系统dualadj.双重的；成双的n.双数dual-sensor复合传感器Dual feedback双反馈dual-thrustn.双推力dual-output双路输出dual carriage双重滑架,双重托架dual-cooledadj.双重冷却的dual symmetry二元对称结构, 回文对称结构dual air pump双空气泵dual-curing双固化dual cylinder双柱