Ⅲ．听短文，根据你所听到的短文内容，选择最佳选项。
11．What did people know little about many years ago?
A．The sun． B．The earth． C．The sun and the earth．
12．The sun goes around the earth, doesn't it?
A．No, it doesn't． B．Yes, it does． C．No, it does．
13．How do you know the earth goes around the sun．
A．Sorry I don’t know．B．With the help of the scientists．
C．Nobody tells me about it．
