已开具的发票存根联和发票登记簿应当保存( )。
A．5年
B．10年
C．15年
D．永久
参考答案：A
______superstitious beliesfs about the mandrake plant.
A．People have had long
B．Have people long had
C．People have long had
D．Long have had people
叉车在磨合后应（）各滤清器的滤芯。
A.清洗
B.更换
C.清洗或更换
D.调整
