当座舱高度达到25000英尺人体的反应是（）.
A.记忆不清，重复同一动作
B.立即昏迷，虚脱
C.生存15秒钟
D.生存3-5分钟
参考答案：B, D
We should not ________ and laugh at those who have no homes to shelter from the rain and wind.
Instead, we should be sympathetic of them.[ ]
A. look forward to
B. think highly of
C. pay attention to
D. look down upon
透明血栓的主要成分是
A．血小板
B．中性粒细胞
C．红细胞
D．纤维蛋白
