宫颈粘液检查见羊齿状结晶提示()
A.体内无雌、孕激素
B.体内有一定量的雌激素
C.体内有一定量的孕激素
D.体内有一定量的雄激素
E.体内有一定量的hCG
参考答案:B
Bad weather prevented the work ____ in time. [ ]
A. completed
B. from completing
C. to be completed
D. being completed
试述现代城市管理具有哪些特征?