建筑地面以上的砌体，宜采用( )。
A．水泥砂浆B．混合砂浆C．石灰砂浆D．石膏砂浆
参考答案：B
There are five pairs ______, but I am at a loss ________.[ ]
A. to choose from, what to buy
B. to choose, which to buy
C. to choose from, which to buy
D. to be chosen, which to buy
在检修带电电气设备时，应有措施，预防人身触电事故。（）
