1--Let's pretend you are in a major U.S. city.
 
2--You are listening to an American English conversation, and you hear this:
 
1--Hey, Bob. Ever since you opened your coffee shop, you have been very busy.
 
2--Is the business going well and making money?
 
1--Yeah! I can't believe it. It's going really well.
 
2--In fact, my coffee shop has become a real cash cow for me.
 
1--How does a cow produce cash?
 
2--Everyone knows cows make milk.
 
1--But in American English, a "cash cow" is a product or service that makes a lot of money for a business.
 
2--This common phrase is used in casual and business conversations.
 
1--And when you use it, everyone will understand what you are saying.
 
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注解：
 
1.conversation对话
2.cash现金
3.common常见的
 
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译文：
 
1--想象一下你现在位于美国的某个大都市：
2--你听到了一段美语对话：
1--嘿，Bob。自从你开了咖啡店以后，你很忙了。
2--生意还好么，赚钱了么？
1--当然！我都无法相信。生意很顺利。
2--事实上，咖啡店变成我真正的摇钱树。（cash cow）
1--奶牛怎么能产生钱呢？
2--我们都是到奶牛是产奶的。
1--但是在美语中，“现金牛”（cash cow）是指一种产品或者服务，能够赚取丰厚的资金。
2--在日常生活和商业环境中，该短语都很常见。
1--当你使用时，大家都能明白你的意思。