master

n.主人；能手；男教师 vt.掌握，精通

masquerader, mass, Mass (also mass), mass communications, mass hysteria, mass media, mass-produce, Massachusetts, massacre, massage, masseur, massif, massive, massively, massiveness, massless, mast, mast-head, mastectomy, mastemaster, master class, Master of Ceremonies, master sergeant, Master's degree (also Master's), master-key, master-stroke, masterful, masterfully, masterly, mastermind, masterpiece, mastery, mastic, masticate, mastication, mastiff, mastitis, mastodon, mastoid, mastoiditis,