If you say that someone is a master of a particular activity, you mean that they are extremely skilled at it.
专家
If you master something, you learn how to do it properly or you succeed in understanding it completely.
掌握• Duff soon mastered the skills of radio production. 达夫很快掌握了广播节目制作的技能。
A master copy of something, such as a film or a tape recording, is an original copy that can be used to produce other copies.
母带的