An open book

An open book （某物）容易理解；（某人）坦诚，没有秘密open adj. 打开的My life is an open book.我的生活很简单。There’s no secret between us, she’s an open book to me.我们之间没有秘密，我对她是了如指掌。I wish these legal contracts were an open book.我真希望我能读懂这些法律合同。Adam says he's an open book, but I've seen him sneaking out of his house late at night. Adam说他没什么秘密，但是我看到过他大半夜偷偷溜出他的房间。