开放性气胸产生纵隔摆动主要是由于()
A.伤侧胸膜腔负压消失
B.呼气与吸气时两例胸膜腔压力差不同
C.健侧胸膜腔负压增加
D.健侧肺萎陷
参考答案:B
Hardly ____ into the country ____ it began to rain.
A. we had got; when
B.we got; than
C. had we got; when
D.did we get; than
—When is your mother's birthday, Tina?
—It's on July the_____.[ ]
A. twenty
B. ninth
C. five