2--Does that mean someone is talking about reading? Let's listen:
 
1--You never have to wonder how megan is feeling.
 
2--It's so easy to read her emotions. She's an open book.
 
1--You are so right. She is easy to read.
 
2--You can always tell if she's having a good day, or a bad day.
 
1--When you say someone is an open book,you mean the person's emotions or thoughts are easy to understand, or as you just heard, easy to read.
 
2--A person who is an open bookdoes not hide secrets well.
 
1--If you have a friend who is easy to read, you can call him or her an open book!
 
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注解：
 
1.conversation会话
2.emotions情绪
3.secrets秘密

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译文：
 
1--下面这个谚语在美式英语对话中，你可能会听到：open book
2--这个短语是不是在说读书的事？一起听一下吧
1--你永远不用去猜测梅根的内心想法。
2--从她的表情中就可以容易地看出她是一个极坦率的人
1--对的！她是一个容易让人读懂的人。
2--你总是能够轻而易举的判断她这天过得开心还是糟糕
1--当你说某人是一个“open book”，你指的是这个人的感情或者想法很容易让人明白，或就像刚才说的那样很容易让人读懂
2--拥有这种性格的人不会适当的隐藏自己的秘密。
1--如果你的朋友当中有人非常坦率，你就可以称他或她为“open book”。