下列关于肺气肿的描述,哪项不正确?
A.肺泡含气量增多
B.肺下界下移
C.肺叩诊过清音
D.心影为靴形
E.肋骨上移,肋间隙增宽
参考答案:D
The bad weather meant ______ the rocket launch (发射) for 48 hours .
A.delaying
B.having delayed
C.to delay
D.to have delayed
经过圆X2+2x+y2=0的圆心C,且与直线x+y=0垂直的直线方程是( )
A.x+y+1=0B.x+y-1=0C.x-y+1=0D.x-y-1=0