风机叶片导叶上的积尘至少应多长时间清扫一次?
参考答案:至少应每半年清扫一次。
She was complaining that the doctor was________too much for the treatment he was giving her.[ ]
A.spending
B.offering
C.costing
D.charging
垄断资本主义的发展为向社会主义过渡准备了物质条件,主要表现在()
A.生产全面社会化
B.生产管理日益社会化
C.工会组织日益社会化
D.资本日益社会化