物体在平面力系作用下处于平衡,就意味着物体相对于地球表面不能有任何运动产生,表示()
A.不能滑动
B.不能移动
C.不能转动
D.不能挪动
E.不能跳动
参考答案:B, C
— Where were you just now?
— I _____________ in the playground.[ ]
A. were
B. was
C. am
硬膜外出血的常见原因是()
A.创伤所致的桥静脉撕裂出血
B.高血压
C.创伤所致的脑膜中动脉撕裂出血
D.动脉瘤
E.胶质瘤