重点讲解：
1. pony up 为…付款；
Each guest had to pony up $40 for the meal.
每位来宾都得为这顿饭付40元#|skv_tc4G38。
2. on average 平均起来；按平均值；
400 people a year die of this disease on average.
平均每年有400人死于这种疾病fJX=t3i,]67。
3. in exchange for 作为交换；
Would you like my old TV in exchange for this camera?
用我的旧电视机换这架照相机，你愿意吗？
4. shut down (使)(工厂、公司等)关闭,歇业，停业；
It is required by law to shut down banks which it regards as chronically short of capital.
法律规定资金长期短缺的银行必须关闭MUT.C_@yk4%dx|g+,o7。