1.a closed book 鲜为人知高深莫测的事；不熟悉的人或物
Skiing is a closed book to me.
我对滑雪是一窍不通。
His early life is a closed book.
他的早年生活是个不可告人的谜.
open book 与第一个习语相反，这个短语表示“众所周知的事或毫无秘密的事”
They have no secrets. He is like an open book to her.
他们之间没有秘密，他对她毫无秘密。
something by the book/go by the book 按规矩做事，循规蹈矩地做事
There is nothing really wrong to go by the book.
一切照规章行事，没有不对的地方。
She does everything by the book.
她做事循规蹈矩，小心谨慎。
someone like a book 看透某人的想法
She couldn't tell a lie if she wanted to. You can always read her like a book.
她想说谎都不行。你总是可以轻易看透她。
I know what he'll probably do. I can read him like a book.
我知道他可能会干什么，我对他了如指掌。
His lie was nailed to the counter cause his mother read him like a book.
他的谎言被揭穿了，因为他妈妈太了解他了。