重點講解：
1. make money
掙錢；賺錢；
eg. They couldn't find work or make money in the cities.
他們在城市找不到工作，也賺不到錢。
eg. He was a businessman, and therefore he always has an eye out for any opportunity to make money.
他是商人，總見錢眼開。
2. down to
只剩下；
eg. The poor man's down to his last £3.
那個可憐的人身上只剩 3 英鎊了。
eg. He was already down to his last loaf of bread.
他已經窮得只剩下最后一個面包了。
3. invest in
購買；買進；
eg. The company invested thousands in an electronic order-control system.
公司耗資數千購買了一套電子訂單管理系統。
eg. The easiest way to make ice cream yourself is to invest in an ice cream machine.
自己制作冰激凌的最簡單的辦法就是買一臺冰激凌機。