— It's dangerous to swim here. Look at the sign.
— Oh, I notice it. Thanks for telling me.
A：haven't
B：won't
C：don't
D：didn't
已知：4x2-1=Ax-1+Bx+1是一个恒等式，则A=____ ，B=____ ．
王某是盐城某一私营企业职工，年终获得3000元的奖金。王某获得的奖金属于_______，这家企业所属的经济成分的地位（作用）是（ ）
