套现是指商户与不良持卡人或其他第三方勾结，或商户自身以虚拟交易套取现金。
参考答案：对
.
. Shanghai is trying to control ________ number of cars on the road to ensure clean air for
________ 2010 World Expo.
A．a ; /
B．a ; the
C．the ; /
D．the ; the
—How much does it cost to build the school library?
—Four _____ yuan. [ ]
A. million
B. millions
C. millions of
D. million of
