经产妇的子宫颈外口呈
A.环形
B.椭圆形
C."+"字形
D."-"字形
E."米"字形
参考答案:D
Don’t worry, sir! All payments ____ be made by the end of the month.
A.will
B.shall
C.can
D.must
下列哪种病毒为缺陷病毒()
A.HAV
B.HBV
C.HCV
D.HDV
E.HEV