通井的三个目的：（）、（）、（）。
参考答案：清除套管壁上杂物、检查套管直径、核实人工井底
用括号内所给词的适当形式填空。
1. Working hard at English _____(lead) to a good job.
2. The movie made me _____(scare).
3. That woman is too lazy _____(cook) the meals every day.
4. Listen!I hear somebody _____(sing) in the next room.
5. By the time we arrived, the meeting _____(be) over.
神经冲动编码信息于
A．锋电位幅度B．动作电位时程C．锋电位传导速度D．动作电位频率E．锋电位传导距离
