为减少身体摆动使重心重新回到双脚范围人体采取的是调节模式是（）
A.踝对策
B.髋对策
C.跨步反应
D.肩对策
E.膝对策
参考答案：B
Where's Tom? His mother ______ him now. [ ]
A. is looking for
B. will look for
C. has looked for
D. looks for
急性左心衰竭主要表现为（）
A.发作性喘息
B.夜间阵发性呼吸困难
C.突发严重呼吸困难
D.进行性加重的呼吸困难
E.劳力性呼吸困难
