下列不能调整叶片频率的方法是()
A.在叶片顶部钻减负荷孔
B.加装拉金
C.减少激振力
D.改变叶片组的叶片数
参考答案:C
王女士,27岁,宫颈黏液分泌减少,而且变得稠厚,此种变化受哪种激素影响()
A.HCG
B.生乳素
C.雌激素
D.孕激素
E.雄激素
He couldn't _____ the fact that the money was found in his house.[ ]
A. answer for
B. leave for
C. account for
D. care for