短語(yǔ)詞組短語(yǔ)back wash line 反洗管線back shoulder line 肩后線back center line 后中線;后中心線back centre line 衙片中心線bring back on line 使復(fù)原back seam line 背縫線back neck line 后領(lǐng)圓線back up line 備份線路back spring line 前倒纜 返回 back line