我国对出口商品实行“征多少，退多少”、“未征不退”和“彻底退税”的原则。
参考答案：对
— Does your mother wash clothes?
— ______________[ ]
A. Yes, she doesn't.
B. Yes, he does.
C. No, she doesn't.
1美元兑换人民币6.2元．用500美元可兑换人民币______元．
