神经纤维传导的特征有（）
A.双向传导
B.相对不疲劳
C.时间延搁
D.可总和
E.绝缘
参考答案：A, B, E
Tom is expecting a pet for long, but his daddy has no time to buy _________ for him.
A．it
B．one
C．this
D．that
常规油藏是指在油藏条件下，原油粘度高于50mpa.s的油藏。（）
