小儿严重的急性肠套叠属于()
A.机械性绞窄性肠梗阻
B.机械性单纯性肠梗阻
C.麻痹性肠梗阻
D.痉挛性肠梗阻
E.血运性肠梗阻
参考答案:A
He spoke loudly to make everybody in the room _______ him clearly.[ ]
A. heard
B. hear
C. to hear
D. hearing
简述中国组织文化的特点。