炉渣的（）是指炉渣所具备的氧化能力大小。
参考答案：氧化性
The flu is believed _______ by viruses that like to reproduce in the cells inside the human nose and throat.
A．causing
B．being caused
C．to be caused
D．be have caused
进入有毒有害物质的设备、容器、下水井（道）内用火时，其工作环境氧含量体积比必须在（）
