be master of ...

phr

• ① 做…的所有者;能自由使用…;通晓…
  • be master of oneself能自制;能独立自主
  • He is total master of the difficult situation.他能完全控制这困难的情势[局面]。
  • She's master of six languages.她通晓六种语言。
  • He is master of a large fortune.他拥有一大笔财富。