a sealed book造句

• Books were beyond her interest-knowledge a sealed book .
  她不喜欢书本，根本谈不到知识。
• Fifteenth - century art was a sealed book to him
  他对15世纪的艺术一无所知。
• I know a little russian , but this is a sealed book to me
  我懂一点俄语，但这种语言对我来说如天书一般难懂。
• It ' s a sealed book to me
  它对我来说是未知的。