Skiing is a closed book to me.

我对滑雪是一窍不通。

Fishing is a closed book to me.

我对钓鱼是一窍不通。

E. g. Music is a closed book to me.

我对音乐一窍不通。

Nuclear physics is a closed book to me.

核物理学是我完全不懂的一门学科.

Of them is like a closed book, with the back uppermost, on which we can read the title of what the book contains.

他们中的每一个都像一本合拢的书，最上面是背面，从那里我们可以读到这本书里所包含的标题。