膝关节属于（）
A.单轴关节
B.双轴关节
C.三轴关节
D.四轴关节
E.复合型关节
参考答案：A
When you are reading fast, your eyes will be one or two word groups ahead ___your mind is taking on.
A．one
B．the others
C．the one
D．others
什幺是油品的粘温性质？
