行驶跑偏的原因有一边制动鼓发咬或轴承（）
A.卡死
B.断裂
C.过紧
D.过松
参考答案：C
25 Last month I came to Britain. My English has improved a lot _______ I use it all the time.
A unless B while C when D as
用霍尔传感器测取电压和电阻反馈信号的优点有哪些？
