be a closed book

To be difficult to know or understand. She's such a private person that I don't know much about her. I guess she's a closed book. I'm a scientist, so art will always be a closed book to me.

be a closed book

to be something that you know or understand nothing about (usually + to ) I'm afraid physics will always be a closed book to me.

Common Names:

Name	Pronounced	Usage
Conchita	kon-CHEE-tah	Spanish
Takuma	tah-koo-mah	Japanese
Coyle	[kɔil]
Raghnall	-	Irish, Scottish
Levente	-	Hungarian
Conley	['kɔnli]