限制性通气不足的主要原因是
A．呼吸肌活动障碍
B．肺泡膜面积减少
C．肺泡膜厚度增加
D．肺泡通气与血流比例失调
E．外周呼吸道阻塞
参考答案：A
I didn’t have a good ______ last night, so I was so _____ that I fell _____ in class.
A．sleep; asleep ;sleepy
B．asleep; sleep; sleepy
C．sleep; sleepy; asleep
D．sleepy; sleep; asleep
