A man escaped from the prison last night. It was a long time ______ the guards discovered what had happened.
A. before
B. until
C. since
D. when
在社会的政治结构中的控制中心是
A. 政治法律制度
B. 政治法律思想
C. 国家政权
D. 政治法律设施
加速资本周转速度,可以增加年剩余价值量和提高年剩余价值率,这是因为
A. 剩余价值率提高了
B. 劳动生产率提高了
C.必要劳动时间缩短了
D. 发挥作用的可变资本数量增加了
______ is known to the world, Beethoven is a great musician.
A. That
B. Which
C. As
D. It