减尘措施是矿井尘害防治工作中最积极、有效的技术措施。
参考答案：对
用氧的指标是机体动脉血氧分压低于（）
A.6.6mmHg
B.6.6mPa
C.6.6kPa
D.66kPa
E.0.66kPa
More than 60 _________ people died in the powerful earthquake (地震) in Sichuan province.[ ]
A. thounnds
B. thousand of
C. thousand
