脊髓空洞症目前治疗情况如何
A．手术治疗
B．放射治疗
C．营养神经
D．康复治疗
E．尚无特效治疗
参考答案：A,B,C,D,E
When I opened the door, I found my father sitting in his chair, completely ______ in a magazine.
A．absorbed
B．focused
C．losing
D．Concentrated
对于河流的简化要求，当河流的断面宽深比( )时，可视为矩形河流。
A．≥5
B．≥10
C．≥20
D．≥40
