一个大一新生的烦恼：

I’m gearing up for my freshman¹ year of college, and I’m trying to decide which language to study. I’d like to pick the language that will be most practical. If you had to pick just one, which would you recommend?

-Freshman

亲爱的艾米莉，

我正在为我的大一生活做准备，并且我在试着选定要学习的语言。我想选一门最实用的语言。如果你要选一门语言来学习的话，你会推荐哪种语言呢？

经济学家Emily Oster的回答：

As someone who took six years of Latin, I am not sure I am the best source for information on what language will be practical, but I’ll give it a try.

作为一个学习了6年拉丁语的人，我不确定自己是否是提供实用语言信息的最佳人选，不过我会试试看。

First, let me say I don’t think you are thinking about this quite the right way. You asked me about what language would be most practical. This suggests you’re thinking about only one side of the choice: the benefit side. Making the optimal² choice requires thinking about both benefits and costs. In this case, I’d argue there may be very different costs to acquiring proficiency³ in different languages. It is a lot harder for most English-speakers to learn Japanese than to learn Spanish.

首先，我得说我认为你考虑问题的方式不对。你问我什么语言最实用，这说明你只考虑了这项选择的一个方面：有益的一面。做出最佳选择需要考虑收益和成本两个方面。在这种情况下，我得说，要熟练掌握不同的语言可能会有不同的代价。对多数讲英语的人而言，学日语就比学西班牙语要困难地多。

But let’s start with the benefits. The benefits of a new language arise from the new people you can interact with in your new language. If maximizing this was your only goal, Mandarin⁴ would be the best choice: This is the native language for 14% of the world’s population, and most of those people do not speak English, so it’s win-win.

不过咱们先说说益处吧。学一门新语言的好处取决于你在学习新语言的过程中可以与之互动的新朋友。如果使这个优势最大化是你唯一的目标，那么普通话会是最佳的选择：这是占世界人口14%的人民的母语，而且他们多数人不讲英语，所以这是一种双赢。

Another language is Spanish, the native language of 5.8% of the world’s population, followed by English, Hindi, and Arabic.

另一种语言就是西班牙语，这是占世界人口5.8%的人民的母语，然后是英语、印地语和阿拉伯语

You might also consider how influential⁵ a given language is likely to be in the future, based on an area’s anticipated economic growth. Mandarin retains an advantage here, given that China is important economically. Spanish has the advantage of being spoken in a larger number of countries, although the total GDP of these countries is less than half that of China alone (roughly $11 trillion in US dollars). On the benefit side, I think we’re down to Mandarin and Spanish.

基于一个地区预期的经济增长，你可能也会考虑特定的语言可能会对你的未来产生多大的影响。鉴于中国在经济上的重要性，在这一方面，普通话依然有优势。西班牙语的优势是更多国家的人讲这门语言，虽然这些国家的国内生产总值合起来还不到中国国内生产总值的一半（约11万亿美元）。在优势这一方面，我认为我们只剩下普通话和西班牙语可以选择了。

On the cost side, Mandarin is a difficult language to learn, particularly as an adult. Learning to say “Ni Hao” and “xiexie” will endear you to a few locals in Shanghai, but it’s unlikely you’ll get far enough in Mandarin to find your knowledge of it truly useful. By contrast, Spanish is considerably⁶ easier for native English speakers, and it’s a lot more likely you’ll reach some level of mastery. In the end, I’d say unless you are a truly gifted linguist⁷, Spanish is the most practical choice.

而在成本这一方面，普通话很难学，特别是对成年人而言。学习说“你好”和“谢谢”可以让上海的一些本地人喜欢你，但是，你对普通话的掌握未必能达到对你真正有用的程度。相比之下，西班牙语对母语是英语的人来说要容易的多，而且你对这门语言的掌握程度更有可能达到精通的水准。最后，我得说，除非你真的是一个语言天才，否则西班牙语会是最实用的选择。

Of course, if you want something which is really useful, you might consider a new computer language, instead. I hear good things about JavaScript.

当然，如果你想学习真正有用的东西，你可以考虑学一门新的计算机语言。我听说JavaScript（一种程序语言）还不错。