下运动神经元
参考答案：
脑神经运动核和脊髓前角内的神经元及其发出的脑神经和脊神经，叫下运动神经元。
To learn to swim well, ___________.
A．one needs much practice
B．much practice is needed
C．much practice needs
D．one is needed much practice
胃特有的运动
A．咀爵B．蠕动C．排空D．袋状往返运动
