说明YT-40*30各符号意义？
参考答案：
Y-单级离心油泵；T-筒型；40-单级扬程；30-级数.
--- ______ her French is so bad?
--- She didn’t seek helpful guidance, I’m afraid.
A．What if
B．What about
C．How come
D．For what
股骨颈囊内骨折较为严重的后期并发症是
A．创伤性关节炎
B．髋关节内翻畸形
C．髋关节屈曲畸形
D．下肢短缩畸形
E．股骨头缺血性坏死
