2--And when you pay for it, you say: This costs me an arm and a leg!
 
1--Do you have to give them your arm and your leg? I hope not.
 
2--Let's listen to an American English conversation to see if we can find out what this means.
 
1--Did you buy that new computer?
 
2--Yeah, I did. And it cost way more than I expected it to.
 
1--How much?
 
2--Let me just tell you it costs an arm and a leg!
 
1--When you say in American English that something costs an arm and a leg, it means that the price is very, very high.
 
2--If you use this phrase, everyone in the United State will understand you.
 
1--But this is an informal phrase, so don't use it in a business setting.
 
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注解：
 
1.costs花费 
2.conversation对话 
3.informal非正式的 

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译文：

1--来讨论一下购物的问题。
2--当你买某件东西时，你说“这花掉了我的一条腿和一只胳膊！”（This costs me an arm and a leg!）
1--你是必须要给一只胳膊和一条腿么？我希望不是真的。
2--让我们来听听下面这段美式英语对话，看看能否明白它真正的意思。
1--你买那台新电脑了么？
2--是的，买了。它比我想象中的贵了很多。
1--多少钱？
2--它花掉了我一只胳膊和一条腿。（it costs an arm and a leg!）
1--当你用美式英语说某物花掉了一只胳膊和一条腿时（something costs an arm and a leg），意思是价格非常、非常高。
2--如果你在美国使用这条短语，大家都会明白你的意思。
1--但是这是个非正式场合用语，所以不要在商务环境下用使用这个短语。