Not Sealed Book, but a few simple English words.

不密封的书，但是一些简单的英国人字。

The origin of the universe is still a sealed book to us.

宇宙的起源对我们来说仍然是不可知的。

Books were beyond her interest — knowledge a sealed book.

她对书本不感兴趣，书本知识和她无缘。

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。

The young generation was always something of a sealed book to Mr Smith.

史密斯先生始终无法了解年轻的一代。