hollows圆角面hollowadj.空的；空洞的；凹陷的；虚伪的；(声音)沉闷的n.山谷；洞；窟窿vt.挖空vi.形成空洞adv.完全地；彻底hollow-shot空心中框Hollow powder空心粉末hollow groove空刀槽hollow billet毛管hollow piston空心活塞Hollow screws空心螺钉hollow needle空心针hollow-core空芯hollow pinion空心齿轴Hollow roller空心滚子