司机不操作方向盘自转,可能出现的原因是下面哪一个()
A、流量放大阀固定螺栓太紧
B、流量放大阀端盖螺栓太紧
C、全液压转向器弹簧片断
参考答案:A
上消化道出血最常见的病因是()
A.肝硬化食管静脉曲张破裂
B.胆道疾病
C.急性糜烂性胃炎
D.消化性溃疡
E.贲门黏膜撕裂症
Mother was busy. Although she was not watching the basketball on TV, she()it on the radio.
A.was listening to
B.was hearing
C.was listening