突然出现片状脱发者为：（）
A.肾虚
B.血虚受风
C.精血不足
D.阴虚火旺
E.津液亏损
参考答案：B
The policeman________the children to cross the road when the traffic lights turned green. [ ]
A. let
B. made
C. signaled
D. called
策划解决方案所需背景信息收集的原则？
