浮选机岗位维护、自修的项目有：（）
A、紧固及更换M30以下螺栓
B、处理槽体、给矿箱漏矿处
C、更换磨损严重的刮板叶片
D、清洗主轴轴承
参考答案：A
The Green Corporation donated the property to the state of California, with one condition _____ the Green
family would be allowed to use it when they wished. [ ]
A. what
B. which
C. when
D. that
概括写出《二十四孝图》作品的内容提要。
