正常人尿液中可见到（）
A.柱状上皮细胞
B.白细胞
C.鳞状上皮细胞
D.吞噬细胞
E.移行上皮细胞
参考答案：B, C, E
—Have you got any particular plans for the coming holiday?
—Yes，________，I’m going to visit some homes for the old in the city.
A．if ever
B．if busy
C．if anything
D．if possible
硅弧焊整流器由哪几部分组成？
