extensionn.延长;伸展;延期;扩充;观念发展;增强n.电话分机;特别课程n.[计]文件名
extension wire补偿导线
extension shoe拉伸蹄片,伸长楦
extension gene扩张基因
extension code扩展码
extension jamb延伸边框
extension bell分铃,分设钟
extension bolt拧接螺栓
extension coil加长线圈,延长线圈
extension bond扩充公司债
extension stem延伸柄,伸缩棒