不插入不穿过松脱退带threading and unthreading operation: 穿带和甩带操作unthreatening: 不具威胁的; 未被胁迫的unthreaded round drill: 无螺纹钻头unthreshed: 未脱粒的unthreaded portion: 无螺纹部分下载手机词典可随时随地查词查翻译