The arm shaft and hook shaft are driven by synchro tooth belt.Knob-type stitch regulator and lever type reverse feeding mechanism permit convenient operation.是什么意思_The arm shaft and hook shaft are driven by synchro tooth belt.Knob-type stitch regulator and lever type reverse feeding mechanism permit convenient operation.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句