慢性阻塞性涎腺炎的主要造影表现是（）
A.主导管扩张
B.主导管呈花边状、羽毛状葱皮状
C.末梢导管扩张
D.腺泡充盈缺损
参考答案：A
It was announced that only when the examination papers were handed in ________to go out of the classroom．
A．the students would be permitted
B．had the students been permitted
C．would the students be permitted
D．the students had been permitted
（）是不承受外来荷载的墙，称为非承重墙。
A、纵墙
B、自承重墙
C、隔墙
D、幕墙
