腰穿的禁忌证是（）。
A.脑动脉硬化
B.神经系统变性病
C.急性脊髓炎
D.后颅窝占位病变
E.神经系统炎症
参考答案：D
—Who do you think will get the first prize?
—Mary, of course. She ________ for the competition for months.
A．is preparing
B．was preparing
C．had been preparing
D．has been preparing
幼儿园保教工作
