<p>Though they are incredibly difficult to learn - Chinese or Hindi would probably become the most advantageous in a business setting. Keep in mind, though that there are many dialects spoken in India so often English is used as the lingua franca. Mandarin Chinese is very difficult to learn - especially the written form.</p>
<p>South Korea has a very vibrant economy that is making itself known in the American business world but it is also difficult. However, the alphabet is phonetic probably making it easier than Mandarin. All three of these options are not simple and for the most part one can assume that businessmen speak English as it is taught in most if not all of the schools.</p>
<p>Brazil also has one of the most rapidly expanding economies right now given the high demand for biofuels and grain worldwide. Linguistically Portuguese is similar to Spanish, so if you are looking for something radically different, Portuguese is not it. You will find a background in Spanish helpful though.</p>
<p>Russian uses Cyrillic making learning it less simple than the Romance languages, but they control many supplies of fossil fuels and I believe that English is less commonly spoken in Russia than most of the previously mentioned areas. </p>
<p>French is diplomatically significant and is useful in Quebec (Canada is our largest trading partner) and sub-Saharan Africa (economically disadvantaged, but full of natural resources). France, Belgium and Switzerland also do a significant amount of trade with the US, but really French is probably most useful because it is a language of the EU (primarily French is spoken in Brussels) and UN. A knowledge of Spanish would be very useful in learning French, but the language certainly has a very different feel.</p>
<p>Germany is an industrial powerhouse and German is supposed to be relatively easy to learn.
Many German firms do business here (BMW, Siemens, Thyssen, etc.)</p>
<p>There would be many benefits in gaining a fluency in Spanish, but if you hate it… Be sure that your problems lie with the language itself and not ALL languages. If you hate tenses and learning vocab. then changing languages will not help you. Think long and hard about quitting Spanish as it is not easy to just pick up another tongue and it does play a big geopolitical role and is especially important within the US as well as south of the border. </p>
<p>I think that you will find that many other parts of the world, especially in business, most people speak English. At least people who a seeking to do business with the US. So really it probably doesn’t matter too terribly much which one you learn. Proficiency in a second language may be the most valuable during the process of hiring rather than doing business due to the proliferation of English in the past several decades across the globe.</p>