榫 榫的英文 英语翻译 tenontenon 拓展翻译 榫槽杆gain pole榫槽接合tongue and groove joint榫搭接joggled lap joint榫接joggling榫接部份ridge榫舌tang; tongue榫头rabbet榫眼mortisemortise榫眼机boring and mortising machine; mortising machine榫子quoin凸榫tenon