为保证神经冲动传递的灵敏性,递质释放后()。
A.不必移除或灭活
B.保持较高浓度
C.必须迅速移除或灭活
D.保持递质恒定
参考答案:C
-Did you watch the football game on TV?
-Yes, I did. I think _________ people also watched it.[ ]
A. several millions
B. millions of
C. two million of
D. two millions