短文改错（共10小题；每小题1分，满分10分）

Never shall I forget the first English lesson giving by Miss Liu. One Monday morning , when she entered into the classroom, we found that she was a young and beautiful lady. Then she introduced her and said they shouldn’t call her Teacher Liu but Miss Liu. Late, she let us go to the blackboard and said something about ourselves in English in turn. When it was my turn, I felt too shy that I didn’t dare to say anything before the class. She went up to me and said kind, “Don’t be afraid. I believe you can do well.” At last, I went to the blackboard. She praised me for that I had done.

下列有关云量的概念，正确的是( )。

A．总云量大于8即为阴天

B．总云量为高云量和低云量之和

C．一般认为总云量大于4即为晴天

D．云以不同的高度分为低云、中云和高云