计算全矿井平均工作面损失率时，式中的“损失量”就是全矿井各工作面（包括报告期内正在开采和开采已结束的）的（）。
参考答案：损失量之和
句型转换,每空一词。
1. Her mother can play the piano.(对画线部分提问)
_____ can her mother _____ ?
2. Our art show needs help.(改为同义句)
We need _____ _____ our art show.
3. Can your aunt help us?(作否定回答)
No, _____ _____ .
4. My cousin plays the guitar very well. (用can改写句子)
My cousin _____ _____ the guitar very well.
5. I want to join the English club.(改为一般疑问句)
_____ _____ want to join the English club?
基础生命支持用药目的是什么
