有效利率是指在复利支付利息条件下的一种复合利率，若已知市场利率是8%，复利每半年支付

患者双小腿伸侧瘙痒，皮损为暗红色浸润斑片，表面无银白色鳞屑，无蜡样光泽，未见粘膜损害，诊断为：

A．水痘
B．传染性软疣
C．扁平疣
D．天疱疮
E．带状疱疹

— He works quite hard.

— Maybe you don't know that he always ____ without asking for leave when he ____ in another company. [ ]

A. went to work; was

B. goes to work; is

C. didn't go to work ; was

D. doesn't go to work; is

Most Asian women try to be shaded from the sun while touring in Europe in summer, fearing that the strong sunshine may ______ the aging process of their skin.

A．accumulate

B．protect

C．accelerate

D．develop

简述假小叶的镜下特点。

RC电路中，时间常数用（）表示，它的大小取决于（）。时间常数越大，电容充（放）过程（）。